diff --git a/patches/api/0004-Code-Generation.patch b/patches/api/0004-Code-Generation.patch
index c19456fe12..68c36e0524 100644
--- a/patches/api/0004-Code-Generation.patch
+++ b/patches/api/0004-Code-Generation.patch
@@ -85,10 +85,10 @@ index 0000000000000000000000000000000000000000..2512dba27edfdccbc4430815b6cba048
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/RegistryKey.java b/src/main/java/io/papermc/paper/registry/RegistryKey.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..1e2765d296decbb3e61b8434e78b5e0214f8fee0
+index 0000000000000000000000000000000000000000..8410d7213370f01cbedbf7fac29bac96f150c49a
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/RegistryKey.java
-@@ -0,0 +1,177 @@
+@@ -0,0 +1,179 @@
 +package io.papermc.paper.registry;
 +
 +import net.kyori.adventure.key.Keyed;
@@ -121,6 +121,7 @@ index 0000000000000000000000000000000000000000..1e2765d296decbb3e61b8434e78b5e02
 +import org.bukkit.potion.PotionEffectType;
 +import org.bukkit.potion.PotionType;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +import static io.papermc.paper.registry.RegistryKeyImpl.create;
 +
@@ -137,6 +138,7 @@ index 0000000000000000000000000000000000000000..1e2765d296decbb3e61b8434e78b5e02
 + * @param <T> the value type
 + */
 +@SuppressWarnings("unused")
++@NullMarked
 +public sealed interface RegistryKey<T> extends Keyed permits RegistryKeyImpl {
 +
 +    /* ******************* *
@@ -268,19 +270,21 @@ index 0000000000000000000000000000000000000000..1e2765d296decbb3e61b8434e78b5e02
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/RegistryKeyImpl.java b/src/main/java/io/papermc/paper/registry/RegistryKeyImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..791813220b2504214b1adecc69093cd600fb0f8c
+index 0000000000000000000000000000000000000000..80e3e64f47ac55a4978c9e5b430e2f2d1c871d1b
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/RegistryKeyImpl.java
-@@ -0,0 +1,24 @@
+@@ -0,0 +1,26 @@
 +package io.papermc.paper.registry;
 +
 +import com.google.common.collect.Sets;
 +import java.util.Set;
 +import net.kyori.adventure.key.Key;
 +import org.intellij.lang.annotations.Subst;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
-+record RegistryKeyImpl<T>(@NotNull Key key) implements RegistryKey<T> {
++@NullMarked
++record RegistryKeyImpl<T>(Key key) implements RegistryKey<T> {
 +
 +    static final Set<RegistryKey<?>> REGISTRY_KEYS = Sets.newIdentityHashSet();
 +
@@ -298,16 +302,16 @@ index 0000000000000000000000000000000000000000..791813220b2504214b1adecc69093cd6
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/TypedKey.java b/src/main/java/io/papermc/paper/registry/TypedKey.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..6f5a062ba7ee7173468ecea3c1855a233bf3855e
+index 0000000000000000000000000000000000000000..cb2e1a4a6d583787573eeefab24e3188c43d148f
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/TypedKey.java
-@@ -0,0 +1,44 @@
+@@ -0,0 +1,45 @@
 +package io.papermc.paper.registry;
 +
 +import net.kyori.adventure.key.Key;
 +import net.kyori.adventure.key.Keyed;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents a key for a value in a specific registry.
@@ -315,6 +319,7 @@ index 0000000000000000000000000000000000000000..6f5a062ba7ee7173468ecea3c1855a23
 + * @param <T> the value type for the registry
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public sealed interface TypedKey<T> extends Keyed permits TypedKeyImpl {
 +
 +    /**
@@ -323,7 +328,7 @@ index 0000000000000000000000000000000000000000..6f5a062ba7ee7173468ecea3c1855a23
 +     * @return the value's key
 +     */
 +    @Override
-+    @NotNull Key key();
++    Key key();
 +
 +    /**
 +     * Gets the registry key for the value this key
@@ -331,7 +336,7 @@ index 0000000000000000000000000000000000000000..6f5a062ba7ee7173468ecea3c1855a23
 +     *
 +     * @return the registry key
 +     */
-+    @NotNull RegistryKey<T> registryKey();
++    RegistryKey<T> registryKey();
 +
 +    /**
 +     * Create a typed key from a key and a registry key.
@@ -342,23 +347,23 @@ index 0000000000000000000000000000000000000000..6f5a062ba7ee7173468ecea3c1855a23
 +     * @return a new key for the value key and registry key
 +     */
 +    @ApiStatus.Experimental
-+    static <T> @NotNull TypedKey<T> create(final @NotNull RegistryKey<T> registryKey, final @NotNull Key key) {
++    static <T> TypedKey<T> create(final RegistryKey<T> registryKey, final Key key) {
 +        return new TypedKeyImpl<>(key, registryKey);
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/TypedKeyImpl.java b/src/main/java/io/papermc/paper/registry/TypedKeyImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..1a97b3359c4ece5c29131da7c3f208aaa8fab66e
+index 0000000000000000000000000000000000000000..99375deaa6b90b33cd6a77e0df651236d304874e
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/TypedKeyImpl.java
 @@ -0,0 +1,8 @@
 +package io.papermc.paper.registry;
 +
 +import net.kyori.adventure.key.Key;
-+import net.kyori.adventure.key.Keyed;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
-+record TypedKeyImpl<T>(@NotNull Key key, @NotNull RegistryKey<T> registryKey) implements TypedKey<T> {
++@NullMarked
++record TypedKeyImpl<T>(Key key, RegistryKey<T> registryKey) implements TypedKey<T> {
 +}
 diff --git a/src/main/java/org/bukkit/MinecraftExperimental.java b/src/main/java/org/bukkit/MinecraftExperimental.java
 index a86b87e4c3332202e40e484c3f9c6562b419c70f..305532968f9f7dd497c77259ed147ea2f081bc74 100644
diff --git a/patches/api/0006-Adventure.patch b/patches/api/0006-Adventure.patch
index a26f91f269..2cfdebf791 100644
--- a/patches/api/0006-Adventure.patch
+++ b/patches/api/0006-Adventure.patch
@@ -91,23 +91,25 @@ index 3383fb91249ea53740326b538abd905f84ff0e3c..74f0e2b812c1e2e922b136fefe505fc8
      doLast {
 diff --git a/src/main/java/io/papermc/paper/chat/ChatRenderer.java b/src/main/java/io/papermc/paper/chat/ChatRenderer.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..ffe0a921cc1ebbb95104f22b57e0e3af85e287a6
+index 0000000000000000000000000000000000000000..1288cdeafe587e9e78e7c5087742ea054ba8423d
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/chat/ChatRenderer.java
-@@ -0,0 +1,71 @@
+@@ -0,0 +1,70 @@
 +package io.papermc.paper.chat;
 +
 +import net.kyori.adventure.audience.Audience;
 +import net.kyori.adventure.text.Component;
 +import org.bukkit.entity.Player;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A chat renderer is responsible for rendering chat messages sent by {@link Player}s to the server.
 + */
++@NullMarked
 +@FunctionalInterface
 +public interface ChatRenderer {
++
 +    /**
 +     * Renders a chat message. This will be called once for each receiving {@link Audience}.
 +     *
@@ -118,15 +120,13 @@ index 0000000000000000000000000000000000000000..ffe0a921cc1ebbb95104f22b57e0e3af
 +     * @return a rendered chat message
 +     */
 +    @ApiStatus.OverrideOnly
-+    @NotNull
-+    Component render(@NotNull Player source, @NotNull Component sourceDisplayName, @NotNull Component message, @NotNull Audience viewer);
++    Component render(Player source, Component sourceDisplayName, Component message, Audience viewer);
 +
 +    /**
 +     * Create a new instance of the default {@link ChatRenderer}.
 +     *
 +     * @return a new {@link ChatRenderer}
 +     */
-+    @NotNull
 +    static ChatRenderer defaultRenderer() {
 +        return new ViewerUnawareImpl.Default((source, sourceDisplayName, message) -> Component.translatable("chat.type.text", sourceDisplayName, message));
 +    }
@@ -142,8 +142,7 @@ index 0000000000000000000000000000000000000000..ffe0a921cc1ebbb95104f22b57e0e3af
 +     * @param renderer the viewer unaware renderer
 +     * @return a new {@link ChatRenderer}
 +     */
-+    @NotNull
-+    static ChatRenderer viewerUnaware(final @NotNull ViewerUnaware renderer) {
++    static ChatRenderer viewerUnaware(final ViewerUnaware renderer) {
 +        return new ViewerUnawareImpl(renderer);
 +    }
 +
@@ -153,6 +152,7 @@ index 0000000000000000000000000000000000000000..ffe0a921cc1ebbb95104f22b57e0e3af
 +     * @see ChatRenderer#viewerUnaware(ViewerUnaware)
 +     */
 +    interface ViewerUnaware {
++
 +        /**
 +         * Renders a chat message.
 +         *
@@ -162,24 +162,26 @@ index 0000000000000000000000000000000000000000..ffe0a921cc1ebbb95104f22b57e0e3af
 +         * @return a rendered chat message
 +         */
 +        @ApiStatus.OverrideOnly
-+        @NotNull
-+        Component render(@NotNull Player source, @NotNull Component sourceDisplayName, @NotNull Component message);
++        Component render(Player source, Component sourceDisplayName, Component message);
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/chat/ViewerUnawareImpl.java b/src/main/java/io/papermc/paper/chat/ViewerUnawareImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..2ad76b1751ba707f7ae0d283aa1cbaf6c9619da9
+index 0000000000000000000000000000000000000000..e1ef23b4bdf60a299d6d37099cef777b3de13ac7
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/chat/ViewerUnawareImpl.java
-@@ -0,0 +1,35 @@
+@@ -0,0 +1,38 @@
 +package io.papermc.paper.chat;
 +
 +import net.kyori.adventure.audience.Audience;
 +import net.kyori.adventure.text.Component;
 +import org.bukkit.entity.Player;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
++@ApiStatus.Internal
++@NullMarked
 +sealed class ViewerUnawareImpl implements ChatRenderer, ChatRenderer.ViewerUnaware permits ViewerUnawareImpl.Default {
 +    private final ViewerUnaware unaware;
 +    private @Nullable Component message;
@@ -189,12 +191,12 @@ index 0000000000000000000000000000000000000000..2ad76b1751ba707f7ae0d283aa1cbaf6
 +    }
 +
 +    @Override
-+    public @NotNull Component render(final @NotNull Player source, final @NotNull Component sourceDisplayName, final @NotNull Component message, final @NotNull Audience viewer) {
++    public Component render(final Player source, final Component sourceDisplayName, final Component message, final Audience viewer) {
 +        return this.render(source, sourceDisplayName, message);
 +    }
 +
 +    @Override
-+    public @NotNull Component render(final @NotNull Player source, final @NotNull Component sourceDisplayName, final @NotNull Component message) {
++    public Component render(final Player source, final Component sourceDisplayName, final Component message) {
 +        if (this.message == null) {
 +            this.message = this.unaware.render(source, sourceDisplayName, message);
 +        }
@@ -579,12 +581,13 @@ index 0000000000000000000000000000000000000000..42a82ce2316a4aad2883d24c7e2ff95d
 +}
 diff --git a/src/main/java/io/papermc/paper/text/PaperComponents.java b/src/main/java/io/papermc/paper/text/PaperComponents.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b9042d0bb
+index 0000000000000000000000000000000000000000..934d1d3ca490a8e25c438bc8c57eb6bde50e0147
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/text/PaperComponents.java
-@@ -0,0 +1,177 @@
+@@ -0,0 +1,180 @@
 +package io.papermc.paper.text;
 +
++import java.io.IOException;
 +import net.kyori.adventure.text.Component;
 +import net.kyori.adventure.text.flattener.ComponentFlattener;
 +import net.kyori.adventure.text.format.NamedTextColor;
@@ -595,15 +598,15 @@ index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b
 +import org.bukkit.Bukkit;
 +import org.bukkit.command.CommandSender;
 +import org.bukkit.entity.Entity;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
-+
-+import java.io.IOException;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Paper API-specific methods for working with {@link Component}s and related.
 + */
++@NullMarked
 +public final class PaperComponents {
++
 +    private PaperComponents() {
 +        throw new RuntimeException("PaperComponents is not to be instantiated!");
 +    }
@@ -633,7 +636,7 @@ index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b
 +     * @return the resolved component
 +     * @throws IOException if a syntax error tripped during resolving
 +     */
-+    public static @NotNull Component resolveWithContext(@NotNull Component input, @Nullable CommandSender context, @Nullable Entity scoreboardSubject) throws IOException {
++    public static Component resolveWithContext(final Component input, final @Nullable CommandSender context, final @Nullable Entity scoreboardSubject) throws IOException {
 +        return resolveWithContext(input, context, scoreboardSubject, true);
 +    }
 +
@@ -664,7 +667,8 @@ index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b
 +     * @return the resolved component
 +     * @throws IOException if a syntax error tripped during resolving
 +     */
-+    public static @NotNull Component resolveWithContext(@NotNull Component input, @Nullable CommandSender context, @Nullable Entity scoreboardSubject, boolean bypassPermissions) throws IOException {
++    @SuppressWarnings("deprecation") // using unsafe as a bridge
++    public static Component resolveWithContext(final Component input, final @Nullable CommandSender context, final @Nullable Entity scoreboardSubject, final boolean bypassPermissions) throws IOException {
 +        return Bukkit.getUnsafe().resolveWithContext(input, context, scoreboardSubject, bypassPermissions);
 +    }
 +
@@ -673,7 +677,8 @@ index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b
 +     *
 +     * @return a component flattener
 +     */
-+    public static @NotNull ComponentFlattener flattener() {
++    @SuppressWarnings("deprecation") // using unsafe as a bridge
++    public static ComponentFlattener flattener() {
 +        return Bukkit.getUnsafe().componentFlattener();
 +    }
 +
@@ -688,7 +693,7 @@ index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b
 +     * @deprecated will be removed in adventure 5.0.0, use {@link PlainTextComponentSerializer#plainText()}
 +     */
 +    @Deprecated(forRemoval = true, since = "1.18.1")
-+    public static @NotNull PlainComponentSerializer plainSerializer() {
++    public static PlainComponentSerializer plainSerializer() {
 +        return Bukkit.getUnsafe().plainComponentSerializer();
 +    }
 +
@@ -703,7 +708,7 @@ index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b
 +     * @deprecated use {@link PlainTextComponentSerializer#plainText()}
 +     */
 +    @Deprecated(forRemoval = true, since = "1.18.2")
-+    public static @NotNull PlainTextComponentSerializer plainTextSerializer() {
++    public static PlainTextComponentSerializer plainTextSerializer() {
 +        return Bukkit.getUnsafe().plainTextSerializer();
 +    }
 +
@@ -719,7 +724,7 @@ index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b
 +     * @deprecated use {@link GsonComponentSerializer#gson()}
 +     */
 +    @Deprecated(forRemoval = true, since = "1.18.2")
-+    public static @NotNull GsonComponentSerializer gsonSerializer() {
++    public static GsonComponentSerializer gsonSerializer() {
 +        return Bukkit.getUnsafe().gsonComponentSerializer();
 +    }
 +
@@ -736,7 +741,7 @@ index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b
 +     * @deprecated use {@link GsonComponentSerializer#colorDownsamplingGson()}
 +     */
 +    @Deprecated(forRemoval = true, since = "1.18.2")
-+    public static @NotNull GsonComponentSerializer colorDownsamplingGsonSerializer() {
++    public static GsonComponentSerializer colorDownsamplingGsonSerializer() {
 +        return Bukkit.getUnsafe().colorDownsamplingGsonComponentSerializer();
 +    }
 +
@@ -756,7 +761,7 @@ index 0000000000000000000000000000000000000000..1a11cfde07db55194cd26757863a268b
 +     * @deprecated use {@link LegacyComponentSerializer#legacySection()}
 +     */
 +    @Deprecated(forRemoval = true, since = "1.18.2")
-+    public static @NotNull LegacyComponentSerializer legacySectionSerializer() {
++    public static LegacyComponentSerializer legacySectionSerializer() {
 +        return Bukkit.getUnsafe().legacyComponentSerializer();
 +    }
 +}
diff --git a/patches/api/0009-Paper-Plugins.patch b/patches/api/0009-Paper-Plugins.patch
index b29d687ccf..bf7455aa11 100644
--- a/patches/api/0009-Paper-Plugins.patch
+++ b/patches/api/0009-Paper-Plugins.patch
@@ -27,26 +27,26 @@ index 1f627e81622e77b81b1228a467fbb9e6fd979e7a..3c50362de25617d878ef58f14f67c240
  
 diff --git a/src/main/java/io/papermc/paper/plugin/PermissionManager.java b/src/main/java/io/papermc/paper/plugin/PermissionManager.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c27846933
+index 0000000000000000000000000000000000000000..c78ada48e27c5552529fe8d5bc23db1dac94e481
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/PermissionManager.java
-@@ -0,0 +1,171 @@
+@@ -0,0 +1,166 @@
 +package io.papermc.paper.plugin;
 +
-+import org.bukkit.permissions.Permissible;
-+import org.bukkit.permissions.Permission;
-+import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
-+
 +import java.util.List;
 +import java.util.Set;
++import org.bukkit.permissions.Permissible;
++import org.bukkit.permissions.Permission;
++import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * A permission manager implementation to keep backwards compatibility partially alive with existing plugins that used
 + * the bukkit one before.
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public interface PermissionManager {
 +
 +    /**
@@ -55,8 +55,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     * @param name Name of the permission
 +     * @return Permission, or null if none
 +     */
-+    @Nullable
-+    Permission getPermission(@NotNull String name);
++    @Nullable Permission getPermission(String name);
 +
 +    /**
 +     * Adds a {@link Permission} to this plugin manager.
@@ -68,7 +67,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     * @throws IllegalArgumentException Thrown when a permission with the same
 +     *                                  name already exists
 +     */
-+    void addPermission(@NotNull Permission perm);
++    void addPermission(Permission perm);
 +
 +    /**
 +     * Removes a {@link Permission} registration from this plugin manager.
@@ -81,7 +80,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     *
 +     * @param perm Permission to remove
 +     */
-+    void removePermission(@NotNull Permission perm);
++    void removePermission(Permission perm);
 +
 +    /**
 +     * Removes a {@link Permission} registration from this plugin manager.
@@ -94,7 +93,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     *
 +     * @param name Permission to remove
 +     */
-+    void removePermission(@NotNull String name);
++    void removePermission(String name);
 +
 +    /**
 +     * Gets the default permissions for the given op status
@@ -102,7 +101,6 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     * @param op Which set of default permissions to get
 +     * @return The default permissions
 +     */
-+    @NotNull
 +    Set<Permission> getDefaultPermissions(boolean op);
 +
 +    /**
@@ -113,7 +111,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     *
 +     * @param perm Permission to recalculate
 +     */
-+    void recalculatePermissionDefaults(@NotNull Permission perm);
++    void recalculatePermissionDefaults(Permission perm);
 +
 +    /**
 +     * Subscribes the given Permissible for information about the requested
@@ -125,7 +123,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     * @param permission  Permission to subscribe to
 +     * @param permissible Permissible subscribing
 +     */
-+    void subscribeToPermission(@NotNull String permission, @NotNull Permissible permissible);
++    void subscribeToPermission(String permission, Permissible permissible);
 +
 +    /**
 +     * Unsubscribes the given Permissible for information about the requested
@@ -134,7 +132,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     * @param permission  Permission to unsubscribe from
 +     * @param permissible Permissible subscribing
 +     */
-+    void unsubscribeFromPermission(@NotNull String permission, @NotNull Permissible permissible);
++    void unsubscribeFromPermission(String permission, Permissible permissible);
 +
 +    /**
 +     * Gets a set containing all subscribed {@link Permissible}s to the given
@@ -143,8 +141,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     * @param permission Permission to query for
 +     * @return Set containing all subscribed permissions
 +     */
-+    @NotNull
-+    Set<Permissible> getPermissionSubscriptions(@NotNull String permission);
++    Set<Permissible> getPermissionSubscriptions(String permission);
 +
 +    /**
 +     * Subscribes to the given Default permissions by operator status
@@ -155,7 +152,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     * @param op          Default list to subscribe to
 +     * @param permissible Permissible subscribing
 +     */
-+    void subscribeToDefaultPerms(boolean op, @NotNull Permissible permissible);
++    void subscribeToDefaultPerms(boolean op, Permissible permissible);
 +
 +    /**
 +     * Unsubscribes from the given Default permissions by operator status
@@ -163,7 +160,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     * @param op          Default list to unsubscribe from
 +     * @param permissible Permissible subscribing
 +     */
-+    void unsubscribeFromDefaultPerms(boolean op, @NotNull Permissible permissible);
++    void unsubscribeFromDefaultPerms(boolean op, Permissible permissible);
 +
 +    /**
 +     * Gets a set containing all subscribed {@link Permissible}s to the given
@@ -172,7 +169,6 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     * @param op Default list to query for
 +     * @return Set containing all subscribed permissions
 +     */
-+    @NotNull
 +    Set<Permissible> getDefaultPermSubscriptions(boolean op);
 +
 +    /**
@@ -182,7 +178,6 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     *
 +     * @return Set containing all current registered permissions
 +     */
-+    @NotNull
 +    Set<Permission> getPermissions();
 +
 +    /**
@@ -192,7 +187,7 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +     *
 +     * @param perm permission
 +     */
-+    void addPermissions(@NotNull List<Permission> perm);
++    void addPermissions(List<Permission> perm);
 +
 +    /**
 +     * Clears the current registered permissinos.
@@ -204,13 +199,14 @@ index 0000000000000000000000000000000000000000..cdbc93b317b3bab47bf6552c29cfbb2c
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/bootstrap/BootstrapContext.java b/src/main/java/io/papermc/paper/plugin/bootstrap/BootstrapContext.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..70d5f9802f90605a5120ff2a000a2e9395f0aecc
+index 0000000000000000000000000000000000000000..4c47414fc08e1183b1e59369bacc4d7f7042f262
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/bootstrap/BootstrapContext.java
-@@ -0,0 +1,14 @@
+@@ -0,0 +1,16 @@
 +package io.papermc.paper.plugin.bootstrap;
 +
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents the context provided to a {@link PluginBootstrap} during both the bootstrapping and plugin
@@ -219,12 +215,13 @@ index 0000000000000000000000000000000000000000..70d5f9802f90605a5120ff2a000a2e93
 + * like the plugin's configuration or logger during the plugins bootstrap.
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface BootstrapContext extends PluginProviderContext {
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/bootstrap/PluginBootstrap.java b/src/main/java/io/papermc/paper/plugin/bootstrap/PluginBootstrap.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..81e09abd2128d8cc54d1fd6454aea7d8d287a11f
+index 0000000000000000000000000000000000000000..e6696dcd8049e869bd1733f7c67ff802c54d7c37
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/bootstrap/PluginBootstrap.java
 @@ -0,0 +1,41 @@
@@ -233,7 +230,7 @@ index 0000000000000000000000000000000000000000..81e09abd2128d8cc54d1fd6454aea7d8
 +import io.papermc.paper.plugin.provider.util.ProviderUtil;
 +import org.bukkit.plugin.java.JavaPlugin;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A plugin bootstrap is meant for loading certain parts of the plugin before the server is loaded.
@@ -245,8 +242,9 @@ index 0000000000000000000000000000000000000000..81e09abd2128d8cc54d1fd6454aea7d8
 + * <p>
 + * <b>All calls to Bukkit may throw a NullPointerExceptions or return null unexpectedly. You should only call api methods that are explicitly documented to work in the bootstrapper</b>
 + */
-+@ApiStatus.OverrideOnly
 +@ApiStatus.Experimental
++@NullMarked
++@ApiStatus.OverrideOnly
 +public interface PluginBootstrap {
 +
 +    /**
@@ -254,7 +252,7 @@ index 0000000000000000000000000000000000000000..81e09abd2128d8cc54d1fd6454aea7d8
 +     *
 +     * @param context the server provided context
 +     */
-+    void bootstrap(@NotNull BootstrapContext context);
++    void bootstrap(BootstrapContext context);
 +
 +    /**
 +     * Called by the server to instantiate your main class.
@@ -264,25 +262,23 @@ index 0000000000000000000000000000000000000000..81e09abd2128d8cc54d1fd6454aea7d8
 +     * @param context the server created bootstrap object
 +     * @return the server requested instance of the plugins main class.
 +     */
-+    @NotNull
-+    default JavaPlugin createPlugin(@NotNull PluginProviderContext context) {
++    default JavaPlugin createPlugin(final PluginProviderContext context) {
 +        return ProviderUtil.loadClass(context.getConfiguration().getMainClass(), JavaPlugin.class, this.getClass().getClassLoader());
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/bootstrap/PluginProviderContext.java b/src/main/java/io/papermc/paper/plugin/bootstrap/PluginProviderContext.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..c1ce2a8bdf2e3bd9ad2fc7f32fba46282bea5d1a
+index 0000000000000000000000000000000000000000..19bb302ab264b72306d9bd15e9c40ade6dde7ee7
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/bootstrap/PluginProviderContext.java
-@@ -0,0 +1,52 @@
+@@ -0,0 +1,48 @@
 +package io.papermc.paper.plugin.bootstrap;
 +
 +import io.papermc.paper.plugin.configuration.PluginMeta;
++import java.nio.file.Path;
 +import net.kyori.adventure.text.logger.slf4j.ComponentLogger;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+
-+import java.nio.file.Path;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents the context provided to a {@link PluginBootstrap} during both the bootstrapping and plugin
@@ -290,8 +286,9 @@ index 0000000000000000000000000000000000000000..c1ce2a8bdf2e3bd9ad2fc7f32fba4628
 + * A bootstrap context may be used to access data or logic usually provided to {@link org.bukkit.plugin.Plugin} instances
 + * like the plugin's configuration or logger during the plugins bootstrap.
 + */
-+@ApiStatus.NonExtendable
 +@ApiStatus.Experimental
++@NullMarked
++@ApiStatus.NonExtendable
 +public interface PluginProviderContext {
 +
 +    /**
@@ -299,7 +296,6 @@ index 0000000000000000000000000000000000000000..c1ce2a8bdf2e3bd9ad2fc7f32fba4628
 +     *
 +     * @return the plugin's configuration
 +     */
-+    @NotNull
 +    PluginMeta getConfiguration();
 +
 +    /**
@@ -307,7 +303,6 @@ index 0000000000000000000000000000000000000000..c1ce2a8bdf2e3bd9ad2fc7f32fba4628
 +     *
 +     * @return the previously described path
 +     */
-+    @NotNull
 +    Path getDataDirectory();
 +
 +    /**
@@ -315,7 +310,6 @@ index 0000000000000000000000000000000000000000..c1ce2a8bdf2e3bd9ad2fc7f32fba4628
 +     *
 +     * @return the logger instance
 +     */
-+    @NotNull
 +    ComponentLogger getLogger();
 +
 +    /**
@@ -323,33 +317,32 @@ index 0000000000000000000000000000000000000000..c1ce2a8bdf2e3bd9ad2fc7f32fba4628
 +     *
 +     * @return the previously described path
 +     */
-+    @NotNull
 +    Path getPluginSource();
 +
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/configuration/PluginMeta.java b/src/main/java/io/papermc/paper/plugin/configuration/PluginMeta.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9ada2e585f
+index 0000000000000000000000000000000000000000..3c768d5ccf490e962d9638e92d4ea7c85670bad8
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/configuration/PluginMeta.java
-@@ -0,0 +1,203 @@
+@@ -0,0 +1,186 @@
 +package io.papermc.paper.plugin.configuration;
 +
++import java.util.List;
 +import org.bukkit.permissions.Permission;
 +import org.bukkit.permissions.PermissionDefault;
 +import org.bukkit.plugin.PluginLoadOrder;
 +import org.bukkit.plugin.java.JavaPlugin;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
-+
-+import java.util.List;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * This class acts as an abstraction for a plugin configuration.
 + */
-+@ApiStatus.NonExtendable
 +@ApiStatus.Experimental // Subject to change!
++@NullMarked
++@ApiStatus.NonExtendable
 +public interface PluginMeta {
 +
 +    /**
@@ -369,7 +362,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return the name of the plugin
 +     */
-+    @NotNull
 +    String getName();
 +
 +    /**
@@ -377,7 +369,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return a descriptive name of the plugin and respective version
 +     */
-+    @NotNull
 +    default String getDisplayName() {
 +        return this.getName() + " v" + this.getVersion();
 +    }
@@ -388,7 +379,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return the fully qualified class name of the plugin's main class.
 +     */
-+    @NotNull
 +    String getMainClass();
 +
 +    /**
@@ -397,7 +387,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     * @return the plugin load order
 +     * @see PluginLoadOrder for further details regards the available load orders.
 +     */
-+    @NotNull
 +    PluginLoadOrder getLoadOrder();
 +
 +    /**
@@ -407,7 +396,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return the string representation of the plugin's version
 +     */
-+    @NotNull
 +    String getVersion();
 +
 +    /**
@@ -418,8 +406,7 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     * @return the specific overwrite of the logger prefix as defined by the plugin. If the plugin did not define a
 +     *     custom logger prefix, this method will return null
 +     */
-+    @Nullable
-+    String getLoggerPrefix();
++    @Nullable String getLoggerPrefix();
 +
 +    /**
 +     * Provides a list of dependencies that are required for this plugin to load.
@@ -430,7 +417,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return an immutable list of required dependency names
 +     */
-+    @NotNull
 +    List<String> getPluginDependencies();
 +
 +    /**
@@ -443,7 +429,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return immutable list of soft dependencies
 +     */
-+    @NotNull
 +    List<String> getPluginSoftDependencies();
 +
 +    /**
@@ -456,7 +441,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return immutable list of plugins to load before this plugin
 +     */
-+    @NotNull
 +    List<String> getLoadBeforePlugins();
 +
 +    /**
@@ -466,7 +450,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return immutable list of provided plugins/dependencies
 +     */
-+    @NotNull
 +    List<String> getProvidedPlugins();
 +
 +    /**
@@ -475,7 +458,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return an immutable list of the plugin's authors
 +     */
-+    @NotNull
 +    List<String> getAuthors();
 +
 +    /**
@@ -484,7 +466,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return an immutable list of the plugin's contributors
 +     */
-+    @NotNull
 +    List<String> getContributors();
 +
 +    /**
@@ -493,8 +474,7 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return description or null if the plugin did not define a human readable description.
 +     */
-+    @Nullable
-+    String getDescription();
++    @Nullable String getDescription();
 +
 +    /**
 +     * Provides the website for the plugin or the plugin's author.
@@ -502,8 +482,7 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     *
 +     * @return a string representation of the website that serves as the main hub for this plugin/its author.
 +     */
-+    @Nullable
-+    String getWebsite();
++    @Nullable String getWebsite();
 +
 +    /**
 +     * Provides the list of permissions that are defined via the plugin meta instance.
@@ -511,7 +490,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     * @return an immutable list of permissions
 +     */
 +    // TODO: Do we even want this? Why not just use the bootstrapper
-+    @NotNull
 +    List<Permission> getPermissions();
 +
 +    /**
@@ -521,7 +499,6 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     * @see #getPermissions()
 +     */
 +    // TODO: Do we even want this? Why not just use the bootstrapper
-+    @NotNull
 +    PermissionDefault getPermissionDefault();
 +
 +    /**
@@ -532,8 +509,7 @@ index 0000000000000000000000000000000000000000..bcf91d048d84144f6acf9bfd2095df9a
 +     * @return the version string made up of the major and minor version (e.g. 1.18 or 1.19). Minor versions like 1.18.2
 +     * are unified to their major release version (in this example 1.18)
 +     */
-+    @Nullable
-+    String getAPIVersion();
++    @Nullable String getAPIVersion();
 +
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/configuration/package-info.java b/src/main/java/io/papermc/paper/plugin/configuration/package-info.java
@@ -552,10 +528,10 @@ index 0000000000000000000000000000000000000000..ddb3076124365d0d1a5caa32d4dcb1f4
 +package io.papermc.paper.plugin.configuration;
 diff --git a/src/main/java/io/papermc/paper/plugin/loader/PluginClasspathBuilder.java b/src/main/java/io/papermc/paper/plugin/loader/PluginClasspathBuilder.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..28cbc09b7c1ded1f4515969cef4a669adac85703
+index 0000000000000000000000000000000000000000..ddb768057cdfd9202e4386494fd5f643692c73a1
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/loader/PluginClasspathBuilder.java
-@@ -0,0 +1,38 @@
+@@ -0,0 +1,37 @@
 +package io.papermc.paper.plugin.loader;
 +
 +import io.papermc.paper.plugin.bootstrap.PluginProviderContext;
@@ -563,14 +539,15 @@ index 0000000000000000000000000000000000000000..28cbc09b7c1ded1f4515969cef4a669a
 +import io.papermc.paper.plugin.loader.library.LibraryStore;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A mutable builder that may be used to collect and register all {@link ClassPathLibrary} instances a
 + * {@link PluginLoader} aims to provide to its plugin at runtime.
 + */
-+@ApiStatus.NonExtendable
 +@ApiStatus.Experimental
++@NullMarked
++@ApiStatus.NonExtendable
 +public interface PluginClasspathBuilder {
 +
 +    /**
@@ -587,23 +564,21 @@ index 0000000000000000000000000000000000000000..28cbc09b7c1ded1f4515969cef4a669a
 +     * @see io.papermc.paper.plugin.loader.library.impl.JarLibrary
 +     * @see io.papermc.paper.plugin.loader.library.impl.MavenLibraryResolver
 +     */
-+    @NotNull
 +    @Contract("_ -> this")
-+    PluginClasspathBuilder addLibrary(@NotNull ClassPathLibrary classPathLibrary);
++    PluginClasspathBuilder addLibrary(ClassPathLibrary classPathLibrary);
 +
-+    @NotNull
 +    PluginProviderContext getContext();
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/loader/PluginLoader.java b/src/main/java/io/papermc/paper/plugin/loader/PluginLoader.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..c9e31f78ff6ff969436c6d99755845786c4d383f
+index 0000000000000000000000000000000000000000..c2d029e4474cc00c84e5b3f7fceec4c3f30b486b
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/loader/PluginLoader.java
-@@ -0,0 +1,30 @@
+@@ -0,0 +1,31 @@
 +package io.papermc.paper.plugin.loader;
 +
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A plugin loader is responsible for creating certain aspects of a plugin before it is created.
@@ -615,8 +590,9 @@ index 0000000000000000000000000000000000000000..c9e31f78ff6ff969436c6d9975584578
 + * It should be noted that this class will be called from a different classloader, this will cause any static values
 + * set in this class/any other classes loaded not to persist when the plugin loads.
 + */
-+@ApiStatus.OverrideOnly
 +@ApiStatus.Experimental
++@NullMarked
++@ApiStatus.OverrideOnly
 +public interface PluginLoader {
 +
 +    /**
@@ -627,23 +603,24 @@ index 0000000000000000000000000000000000000000..c9e31f78ff6ff969436c6d9975584578
 +     * @param classpathBuilder a mutable classpath builder that may be used to register custom runtime dependencies
 +     *                         for the plugin the loader was registered for.
 +     */
-+    void classloader(@NotNull PluginClasspathBuilder classpathBuilder);
++    void classloader(PluginClasspathBuilder classpathBuilder);
 +
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/loader/library/ClassPathLibrary.java b/src/main/java/io/papermc/paper/plugin/loader/library/ClassPathLibrary.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..1347b535d90c2c281c184d0459e7ac59c0350c9f
+index 0000000000000000000000000000000000000000..8a07333a592056bab1d26d811316bb5ea5f30e18
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/loader/library/ClassPathLibrary.java
-@@ -0,0 +1,20 @@
+@@ -0,0 +1,21 @@
 +package io.papermc.paper.plugin.loader.library;
 +
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * The classpath library interface represents libraries that are capable of registering themselves via
 + * {@link #register(LibraryStore)} on any given {@link LibraryStore}.
 + */
++@NullMarked
 +public interface ClassPathLibrary {
 +
 +    /**
@@ -654,7 +631,7 @@ index 0000000000000000000000000000000000000000..1347b535d90c2c281c184d0459e7ac59
 +     * @param store the library store instance to register this library into
 +     * @throws LibraryLoadingException if library loading failed for this classpath library
 +     */
-+    void register(@NotNull LibraryStore store) throws LibraryLoadingException;
++    void register(LibraryStore store) throws LibraryLoadingException;
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/loader/library/LibraryLoadingException.java b/src/main/java/io/papermc/paper/plugin/loader/library/LibraryLoadingException.java
 new file mode 100644
@@ -679,16 +656,15 @@ index 0000000000000000000000000000000000000000..79ba423a364b50588f3ee87fdc69155c
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/loader/library/LibraryStore.java b/src/main/java/io/papermc/paper/plugin/loader/library/LibraryStore.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..0546fa1e9dcd7155086a8650806a8c086b6fc458
+index 0000000000000000000000000000000000000000..93ef8e369a158c25bc4fdd553faf13c1826ad872
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/loader/library/LibraryStore.java
 @@ -0,0 +1,26 @@
 +package io.papermc.paper.plugin.loader.library;
 +
-+import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+
 +import java.nio.file.Path;
++import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents a storage that stores library jars.
@@ -699,6 +675,7 @@ index 0000000000000000000000000000000000000000..0546fa1e9dcd7155086a8650806a8c08
 + * @see io.papermc.paper.plugin.loader.PluginLoader
 + */
 +@ApiStatus.Internal
++@NullMarked
 +public interface LibraryStore {
 +
 +    /**
@@ -706,12 +683,12 @@ index 0000000000000000000000000000000000000000..0546fa1e9dcd7155086a8650806a8c08
 +     *
 +     * @param library path to the libraries jar file on the disk
 +     */
-+    void addLibrary(@NotNull Path library);
++    void addLibrary(Path library);
 +
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/loader/library/impl/JarLibrary.java b/src/main/java/io/papermc/paper/plugin/loader/library/impl/JarLibrary.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..e3da0d67cab01e1233dccde1a12ff25961ee79fb
+index 0000000000000000000000000000000000000000..9efcd9a62d6439eb27fc4e08498b4b7fbbdecb3c
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/loader/library/impl/JarLibrary.java
 @@ -0,0 +1,45 @@
@@ -720,10 +697,9 @@ index 0000000000000000000000000000000000000000..e3da0d67cab01e1233dccde1a12ff259
 +import io.papermc.paper.plugin.loader.library.ClassPathLibrary;
 +import io.papermc.paper.plugin.loader.library.LibraryLoadingException;
 +import io.papermc.paper.plugin.loader.library.LibraryStore;
-+import org.jetbrains.annotations.NotNull;
-+
 +import java.nio.file.Files;
 +import java.nio.file.Path;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A simple jar library implementation of the {@link ClassPathLibrary} that allows {@link io.papermc.paper.plugin.loader.PluginLoader}s to
@@ -738,6 +714,7 @@ index 0000000000000000000000000000000000000000..e3da0d67cab01e1233dccde1a12ff259
 + * <p>
 + * The jar library implementation will error if the file does not exist at the specified path.
 + */
++@NullMarked
 +public class JarLibrary implements ClassPathLibrary {
 +
 +    private final Path path;
@@ -747,12 +724,12 @@ index 0000000000000000000000000000000000000000..e3da0d67cab01e1233dccde1a12ff259
 +     *
 +     * @param path the path, relative to the JVMs start directory.
 +     */
-+    public JarLibrary(@NotNull Path path) {
++    public JarLibrary(final Path path) {
 +        this.path = path;
 +    }
 +
 +    @Override
-+    public void register(@NotNull LibraryStore store) throws LibraryLoadingException {
++    public void register(final LibraryStore store) throws LibraryLoadingException {
 +        if (Files.notExists(this.path)) {
 +            throw new LibraryLoadingException("Could not find library at " + this.path);
 +        }
@@ -762,7 +739,7 @@ index 0000000000000000000000000000000000000000..e3da0d67cab01e1233dccde1a12ff259
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/loader/library/impl/MavenLibraryResolver.java b/src/main/java/io/papermc/paper/plugin/loader/library/impl/MavenLibraryResolver.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..70f352630de71f575d1aea5a3126da19a94791ab
+index 0000000000000000000000000000000000000000..107705db2d82b7c191e5e625ec888e0bc3b03831
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/loader/library/impl/MavenLibraryResolver.java
 @@ -0,0 +1,133 @@
@@ -771,6 +748,9 @@ index 0000000000000000000000000000000000000000..70f352630de71f575d1aea5a3126da19
 +import io.papermc.paper.plugin.loader.library.ClassPathLibrary;
 +import io.papermc.paper.plugin.loader.library.LibraryLoadingException;
 +import io.papermc.paper.plugin.loader.library.LibraryStore;
++import java.io.File;
++import java.util.ArrayList;
++import java.util.List;
 +import org.apache.maven.repository.internal.MavenRepositorySystemUtils;
 +import org.eclipse.aether.DefaultRepositorySystemSession;
 +import org.eclipse.aether.RepositorySystem;
@@ -791,14 +771,10 @@ index 0000000000000000000000000000000000000000..70f352630de71f575d1aea5a3126da19
 +import org.eclipse.aether.transfer.TransferCancelledException;
 +import org.eclipse.aether.transfer.TransferEvent;
 +import org.eclipse.aether.transport.http.HttpTransporterFactory;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +import org.slf4j.Logger;
 +import org.slf4j.LoggerFactory;
 +
-+import java.io.File;
-+import java.util.ArrayList;
-+import java.util.List;
-+
 +/**
 + * The maven library resolver acts as a resolver for yet to be resolved jar libraries that may be pulled from a
 + * remote maven repository.
@@ -813,12 +789,13 @@ index 0000000000000000000000000000000000000000..70f352630de71f575d1aea5a3126da19
 + *     "central", "default", "https://repo1.maven.org/maven2/"
 + * ).build());
 + * }</pre>
-+ *
++ * <p>
 + * Plugins may create and register a {@link MavenLibraryResolver} after configuring it.
 + */
++@NullMarked
 +public class MavenLibraryResolver implements ClassPathLibrary {
 +
-+    private static final Logger logger = LoggerFactory.getLogger("MavenLibraryResolver");
++    private static final Logger LOGGER = LoggerFactory.getLogger("MavenLibraryResolver");
 +
 +    private final RepositorySystem repository;
 +    private final DefaultRepositorySystemSession session;
@@ -834,7 +811,7 @@ index 0000000000000000000000000000000000000000..70f352630de71f575d1aea5a3126da19
 +     * submitting the {@link MavenLibraryResolver} to the {@link io.papermc.paper.plugin.loader.PluginClasspathBuilder}.
 +     */
 +    public MavenLibraryResolver() {
-+        DefaultServiceLocator locator = MavenRepositorySystemUtils.newServiceLocator();
++        final DefaultServiceLocator locator = MavenRepositorySystemUtils.newServiceLocator();
 +        locator.addService(RepositoryConnectorFactory.class, BasicRepositoryConnectorFactory.class);
 +        locator.addService(TransporterFactory.class, HttpTransporterFactory.class);
 +
@@ -846,8 +823,8 @@ index 0000000000000000000000000000000000000000..70f352630de71f575d1aea5a3126da19
 +        this.session.setLocalRepositoryManager(this.repository.newLocalRepositoryManager(this.session, new LocalRepository("libraries")));
 +        this.session.setTransferListener(new AbstractTransferListener() {
 +            @Override
-+            public void transferInitiated(@NotNull TransferEvent event) throws TransferCancelledException {
-+                logger.info("Downloading {}", event.getResource().getRepositoryUrl() + event.getResource().getResourceName());
++            public void transferInitiated(final TransferEvent event) throws TransferCancelledException {
++                LOGGER.info("Downloading {}", event.getResource().getRepositoryUrl() + event.getResource().getResourceName());
 +            }
 +        });
 +        this.session.setReadOnly();
@@ -860,7 +837,7 @@ index 0000000000000000000000000000000000000000..70f352630de71f575d1aea5a3126da19
 +     * @param dependency the definition of the dependency the maven library resolver should resolve when running
 +     * @see MavenLibraryResolver#addRepository(RemoteRepository)
 +     */
-+    public void addDependency(@NotNull Dependency dependency) {
++    public void addDependency(final Dependency dependency) {
 +        this.dependencies.add(dependency);
 +    }
 +
@@ -870,9 +847,9 @@ index 0000000000000000000000000000000000000000..70f352630de71f575d1aea5a3126da19
 +     * repository.
 +     *
 +     * @param remoteRepository the configuration that defines the maven repository this library resolver should fetch
-+     *                         dependencies from
++     * dependencies from
 +     */
-+    public void addRepository(@NotNull RemoteRepository remoteRepository) {
++    public void addRepository(final RemoteRepository remoteRepository) {
 +        this.repositories.add(remoteRepository);
 +    }
 +
@@ -883,32 +860,32 @@ index 0000000000000000000000000000000000000000..70f352630de71f575d1aea5a3126da19
 +     * @throws LibraryLoadingException if resolving a dependency failed
 +     */
 +    @Override
-+    public void register(@NotNull LibraryStore store) throws LibraryLoadingException {
-+        List<RemoteRepository> repos = this.repository.newResolutionRepositories(this.session, this.repositories);
++    public void register(final LibraryStore store) throws LibraryLoadingException {
++        final List<RemoteRepository> repos = this.repository.newResolutionRepositories(this.session, this.repositories);
 +
-+        DependencyResult result;
++        final DependencyResult result;
 +        try {
 +            result = this.repository.resolveDependencies(this.session, new DependencyRequest(new CollectRequest((Dependency) null, this.dependencies, repos), null));
-+        } catch (DependencyResolutionException ex) {
++        } catch (final DependencyResolutionException ex) {
 +            throw new LibraryLoadingException("Error resolving libraries", ex);
 +        }
 +
-+        for (ArtifactResult artifact : result.getArtifactResults()) {
-+            File file = artifact.getArtifact().getFile();
++        for (final ArtifactResult artifact : result.getArtifactResults()) {
++            final File file = artifact.getArtifact().getFile();
 +            store.addLibrary(file.toPath());
 +        }
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/provider/classloader/ClassLoaderAccess.java b/src/main/java/io/papermc/paper/plugin/provider/classloader/ClassLoaderAccess.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..64e46fdfa4d404cb08c67a456e5990b729296b98
+index 0000000000000000000000000000000000000000..75fe408ec742319c3cba2461b33b2a6e8b22d231
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/provider/classloader/ClassLoaderAccess.java
-@@ -0,0 +1,34 @@
+@@ -0,0 +1,35 @@
 +package io.papermc.paper.plugin.provider.classloader;
 +
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * The class loader access interface is an <b>internal</b> representation of a class accesses' ability to see types
@@ -919,6 +896,7 @@ index 0000000000000000000000000000000000000000..64e46fdfa4d404cb08c67a456e5990b7
 + * is owned by a direct or transitive dependency of the plugin, preventing the plugin for accidentally discovering and
 + * using class types that are supplied by plugins/libraries the plugin did not actively define as a dependency.
 + */
++@NullMarked
 +@ApiStatus.Internal
 +public interface ClassLoaderAccess {
 +
@@ -941,19 +919,18 @@ index 0000000000000000000000000000000000000000..64e46fdfa4d404cb08c67a456e5990b7
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/provider/classloader/ConfiguredPluginClassLoader.java b/src/main/java/io/papermc/paper/plugin/provider/classloader/ConfiguredPluginClassLoader.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..a21bdc57564aef7caf43dde3b2bcb2fc7f30461c
+index 0000000000000000000000000000000000000000..7c23e0a1a38f8b89484aee160647f751088903cd
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/provider/classloader/ConfiguredPluginClassLoader.java
-@@ -0,0 +1,71 @@
+@@ -0,0 +1,70 @@
 +package io.papermc.paper.plugin.provider.classloader;
 +
 +import io.papermc.paper.plugin.configuration.PluginMeta;
++import java.io.Closeable;
 +import org.bukkit.plugin.java.JavaPlugin;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+
-+import java.io.Closeable;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * The configured plugin class loader represents an <b>internal</b> abstraction over the classloaders used by the server
@@ -962,6 +939,7 @@ index 0000000000000000000000000000000000000000..a21bdc57564aef7caf43dde3b2bcb2fc
 + * It implements {@link Closeable} to define the ability to shutdown and close the classloader that implements this
 + * interface.
 + */
++@NullMarked
 +@ApiStatus.Internal
 +public interface ConfiguredPluginClassLoader extends Closeable {
 +
@@ -987,7 +965,7 @@ index 0000000000000000000000000000000000000000..a21bdc57564aef7caf43dde3b2bcb2fc
 +     * @see ClassLoader#loadClass(String)
 +     * @see Class#forName(String, boolean, ClassLoader)
 +     */
-+    Class<?> loadClass(@NotNull String name,
++    Class<?> loadClass(String name,
 +                       boolean resolve,
 +                       boolean checkGlobal,
 +                       boolean checkLibraries) throws ClassNotFoundException;
@@ -1013,8 +991,7 @@ index 0000000000000000000000000000000000000000..a21bdc57564aef7caf43dde3b2bcb2fc
 +     * that is used by the underlying classloader
 +     * @return classloader
 +     */
-+    @Nullable
-+    PluginClassLoaderGroup getGroup();
++    @Nullable PluginClassLoaderGroup getGroup();
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/provider/classloader/PaperClassLoaderStorage.java b/src/main/java/io/papermc/paper/plugin/provider/classloader/PaperClassLoaderStorage.java
 new file mode 100644
@@ -1139,15 +1116,16 @@ index 0000000000000000000000000000000000000000..2c0e5ba6f8eba7a632180491843071b8
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/provider/classloader/PluginClassLoaderGroup.java b/src/main/java/io/papermc/paper/plugin/provider/classloader/PluginClassLoaderGroup.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..885151cb932d9b8c09a7887edc879e154225f416
+index 0000000000000000000000000000000000000000..dd3bfbf8a30c9ac6a82dcbdf879bbf120d920e20
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/provider/classloader/PluginClassLoaderGroup.java
-@@ -0,0 +1,65 @@
+@@ -0,0 +1,66 @@
 +package io.papermc.paper.plugin.provider.classloader;
 +
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * A plugin classloader group represents a group of classloaders that a plugins classloader may access.
@@ -1155,6 +1133,7 @@ index 0000000000000000000000000000000000000000..885151cb932d9b8c09a7887edc879e15
 + * An example of this would be a classloader group that holds all direct and transitive dependencies a plugin declared,
 + * allowing a plugins classloader to access classes included in these dependencies via this group.
 + */
++@NullMarked
 +@ApiStatus.Internal
 +public interface PluginClassLoaderGroup {
 +
@@ -1172,8 +1151,7 @@ index 0000000000000000000000000000000000000000..885151cb932d9b8c09a7887edc879e15
 +     * will be returned.
 +     * @see ConfiguredPluginClassLoader#loadClass(String, boolean, boolean, boolean)
 +     */
-+    @Nullable
-+    Class<?> getClassByName(String name, boolean resolve, ConfiguredPluginClassLoader requester);
++    @Nullable Class<?> getClassByName(String name, boolean resolve, ConfiguredPluginClassLoader requester);
 +
 +    /**
 +     * Removes a configured plugin classloader from this class loader group.
@@ -1210,15 +1188,15 @@ index 0000000000000000000000000000000000000000..885151cb932d9b8c09a7887edc879e15
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/provider/entrypoint/DependencyContext.java b/src/main/java/io/papermc/paper/plugin/provider/entrypoint/DependencyContext.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..44d630c3eb2670c36134b9907519dc986b3761b4
+index 0000000000000000000000000000000000000000..338dc25d5161b7378dd17b17d6f603c92eb0a894
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/provider/entrypoint/DependencyContext.java
-@@ -0,0 +1,48 @@
+@@ -0,0 +1,49 @@
 +package io.papermc.paper.plugin.provider.entrypoint;
 +
 +import io.papermc.paper.plugin.configuration.PluginMeta;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A dependency context is a read-only abstraction of a type/concept that can resolve dependencies between plugins.
@@ -1226,6 +1204,7 @@ index 0000000000000000000000000000000000000000..44d630c3eb2670c36134b9907519dc98
 + * This may for example be the server wide plugin manager itself, capable of validating if a dependency exists between
 + * two {@link PluginMeta} instances, however the implementation is not limited to such a concrete use-case.
 + */
++@NullMarked
 +@ApiStatus.Internal
 +public interface DependencyContext {
 +
@@ -1245,7 +1224,7 @@ index 0000000000000000000000000000000000000000..44d630c3eb2670c36134b9907519dc98
 +     * @param depend the potential transitive dependency of the {@code plugin} parameter.
 +     * @return a simple boolean flag indicating if {@code plugin} considers {@code depend} as a transitive dependency.
 +     */
-+    boolean isTransitiveDependency(@NotNull PluginMeta plugin, @NotNull PluginMeta depend);
++    boolean isTransitiveDependency(PluginMeta plugin, PluginMeta depend);
 +
 +    /**
 +     * Computes if this dependency context is aware of a dependency that provides/matches the passed identifier.
@@ -1259,29 +1238,30 @@ index 0000000000000000000000000000000000000000..44d630c3eb2670c36134b9907519dc98
 +     * @return a plain boolean flag indicating if this dependency context is aware of a potential dependency with the
 +     * passed identifier.
 +     */
-+    boolean hasDependency(@NotNull String pluginIdentifier);
++    boolean hasDependency(String pluginIdentifier);
 +
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/provider/util/ProviderUtil.java b/src/main/java/io/papermc/paper/plugin/provider/util/ProviderUtil.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..6bf3d212a6156ad9ab0e82d1ca0a04f83f6e4b83
+index 0000000000000000000000000000000000000000..48a67c1b6070292dbf4ea3081f89b530207f9f6d
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/provider/util/ProviderUtil.java
-@@ -0,0 +1,78 @@
+@@ -0,0 +1,77 @@
 +package io.papermc.paper.plugin.provider.util;
 +
 +import com.destroystokyo.paper.util.SneakyThrow;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * An <b>internal</b> utility type that holds logic for loading a provider-like type from a classloaders.
 + * Provides, at least in the context of this utility, define themselves as implementations of a specific parent
 + * interface/type, e.g. {@link org.bukkit.plugin.java.JavaPlugin} and implement a no-args constructor.
 + */
++@NullMarked
 +@ApiStatus.Internal
-+public class ProviderUtil {
++public final class ProviderUtil {
 +
 +    /**
 +     * Loads the class found at the provided fully qualified class name from the passed classloader, creates a new
@@ -1294,8 +1274,7 @@ index 0000000000000000000000000000000000000000..6bf3d212a6156ad9ab0e82d1ca0a04f8
 +     * @param <T>       the generic type of the parent class the created object will be cast to
 +     * @return the object instantiated from the class found at the provided FQN, cast to the parent type
 +     */
-+    @NotNull
-+    public static <T> T loadClass(@NotNull String clazz, @NotNull Class<T> classType, @NotNull ClassLoader loader) {
++    public static <T> T loadClass(final String clazz, final Class<T> classType, final ClassLoader loader) {
 +        return loadClass(clazz, classType, loader, null);
 +    }
 +
@@ -1312,30 +1291,29 @@ index 0000000000000000000000000000000000000000..6bf3d212a6156ad9ab0e82d1ca0a04f8
 +     * @return the object instantiated from the class found at the provided fully qualified class name, cast to the
 +     * parent type
 +     */
-+    @NotNull
-+    public static <T> T loadClass(@NotNull String clazz, @NotNull Class<T> classType, @NotNull ClassLoader loader, @Nullable Runnable onError) {
++    public static <T> T loadClass(final String clazz, final Class<T> classType, final ClassLoader loader, final @Nullable Runnable onError) {
 +        try {
-+            T clazzInstance;
++            final T clazzInstance;
 +
 +            try {
-+                Class<?> jarClass = Class.forName(clazz, true, loader);
++                final Class<?> jarClass = Class.forName(clazz, true, loader);
 +
-+                Class<? extends T> pluginClass;
++                final Class<? extends T> pluginClass;
 +                try {
 +                    pluginClass = jarClass.asSubclass(classType);
-+                } catch (ClassCastException ex) {
++                } catch (final ClassCastException ex) {
 +                    throw new ClassCastException("class '%s' does not extend '%s'".formatted(clazz, classType));
 +                }
 +
 +                clazzInstance = pluginClass.getDeclaredConstructor().newInstance();
-+            } catch (IllegalAccessException exception) {
++            } catch (final IllegalAccessException exception) {
 +                throw new RuntimeException("No public constructor");
-+            } catch (InstantiationException exception) {
++            } catch (final InstantiationException exception) {
 +                throw new RuntimeException("Abnormal class instantiation", exception);
 +            }
 +
 +            return clazzInstance;
-+        } catch (Throwable e) {
++        } catch (final Throwable e) {
 +            if (onError != null) {
 +                onError.run();
 +            }
diff --git a/patches/api/0010-Add-Position.patch b/patches/api/0010-Add-Position.patch
index c56e4e0a0e..2e4718c86b 100644
--- a/patches/api/0010-Add-Position.patch
+++ b/patches/api/0010-Add-Position.patch
@@ -6,25 +6,27 @@ Subject: [PATCH] Add Position
 
 diff --git a/src/main/java/io/papermc/paper/math/BlockPosition.java b/src/main/java/io/papermc/paper/math/BlockPosition.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..f0fdabce4af640da2a406412e67020761ded3ac1
+index 0000000000000000000000000000000000000000..c358bfdefc9bc7598dbd0d89a6b0b8a9408b5bb3
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/math/BlockPosition.java
-@@ -0,0 +1,98 @@
+@@ -0,0 +1,100 @@
 +package io.papermc.paper.math;
 +
 +import org.bukkit.Axis;
 +import org.bukkit.block.BlockFace;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A position represented with integers.
 + * <p>
 + * <b>May see breaking changes until Experimental annotation is removed.</b>
++ *
 + * @see FinePosition
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public interface BlockPosition extends Position {
 +
 +    @Override
@@ -53,17 +55,17 @@ index 0000000000000000000000000000000000000000..f0fdabce4af640da2a406412e6702076
 +    }
 +
 +    @Override
-+    default @NotNull BlockPosition toBlock() {
++    default BlockPosition toBlock() {
 +        return this;
 +    }
 +
 +    @Override
-+    default @NotNull BlockPosition offset(int x, int y, int z) {
++    default BlockPosition offset(final int x, final int y, final int z) {
 +        return x == 0 && y == 0 && z == 0 ? this : new BlockPositionImpl(this.blockX() + x, this.blockY() + y, this.blockZ() + z);
 +    }
 +
 +    @Override
-+    default @NotNull FinePosition offset(double x, double y, double z) {
++    default FinePosition offset(final double x, final double y, final double z) {
 +        return new FinePositionImpl(this.blockX() + x, this.blockY() + y, this.blockZ() + z);
 +    }
 +
@@ -74,7 +76,7 @@ index 0000000000000000000000000000000000000000..f0fdabce4af640da2a406412e6702076
 +     * @return the offset block position
 +     */
 +    @Contract(value = "_ -> new", pure = true)
-+    default @NotNull BlockPosition offset(@NotNull BlockFace blockFace) {
++    default BlockPosition offset(final BlockFace blockFace) {
 +        return this.offset(blockFace, 1);
 +    }
 +
@@ -87,7 +89,7 @@ index 0000000000000000000000000000000000000000..f0fdabce4af640da2a406412e6702076
 +     * @return the offset block position
 +     */
 +    @Contract(pure = true)
-+    default @NotNull BlockPosition offset(@NotNull BlockFace blockFace, int amount) {
++    default BlockPosition offset(final BlockFace blockFace, final int amount) {
 +        return amount == 0 ? this : new BlockPositionImpl(this.blockX() + (blockFace.getModX() * amount), this.blockY() + (blockFace.getModY() * amount), this.blockZ() + (blockFace.getModZ() * amount));
 +    }
 +
@@ -100,7 +102,7 @@ index 0000000000000000000000000000000000000000..f0fdabce4af640da2a406412e6702076
 +     * @return the offset block position
 +     */
 +    @Contract(pure = true)
-+    default @NotNull BlockPosition offset(@NotNull Axis axis, int amount) {
++    default BlockPosition offset(final Axis axis, final int amount) {
 +        return amount == 0 ? this : switch (axis) {
 +            case X -> new BlockPositionImpl(this.blockX() + amount, this.blockY(), this.blockZ());
 +            case Y -> new BlockPositionImpl(this.blockX(), this.blockY() + amount, this.blockZ());
@@ -120,24 +122,25 @@ index 0000000000000000000000000000000000000000..eb5a3f26c7ba56c6715827f52c0013a8
 +}
 diff --git a/src/main/java/io/papermc/paper/math/FinePosition.java b/src/main/java/io/papermc/paper/math/FinePosition.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..d8df70d731573cf2446044925f218876d62fd7cf
+index 0000000000000000000000000000000000000000..b9c0065d8a9dedc3bd1a2d8bfbedfbc7f952ff93
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/math/FinePosition.java
-@@ -0,0 +1,56 @@
+@@ -0,0 +1,57 @@
 +package io.papermc.paper.math;
 +
 +import org.bukkit.util.NumberConversions;
-+import org.bukkit.util.Vector;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A position represented with doubles.
 + * <p>
 + * <b>May see breaking changes until Experimental annotation is removed.</b>
++ *
 + * @see BlockPosition
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public interface FinePosition extends Position {
 +
 +    @Override
@@ -166,17 +169,17 @@ index 0000000000000000000000000000000000000000..d8df70d731573cf2446044925f218876
 +    }
 +
 +    @Override
-+    default @NotNull BlockPosition toBlock() {
++    default BlockPosition toBlock() {
 +        return new BlockPositionImpl(this.blockX(), this.blockY(), this.blockZ());
 +    }
 +
 +    @Override
-+    default @NotNull FinePosition offset(int x, int y, int z) {
++    default FinePosition offset(final int x, final int y, final int z) {
 +        return this.offset((double) x, y, z);
 +    }
 +
 +    @Override
-+    default @NotNull FinePosition offset(double x, double y, double z) {
++    default FinePosition offset(final double x, final double y, final double z) {
 +        return x == 0.0 && y == 0.0 && z == 0.0 ? this : new FinePositionImpl(this.x() + x, this.y() + y, this.z() + z);
 +    }
 +}
@@ -192,10 +195,10 @@ index 0000000000000000000000000000000000000000..93476aaf8d21efb5a30b6d2cc2eeda81
 +}
 diff --git a/src/main/java/io/papermc/paper/math/Position.java b/src/main/java/io/papermc/paper/math/Position.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d9f242740
+index 0000000000000000000000000000000000000000..0e6a6a6738353b118e0ed093994dda06750700c4
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/math/Position.java
-@@ -0,0 +1,191 @@
+@@ -0,0 +1,192 @@
 +package io.papermc.paper.math;
 +
 +import org.bukkit.Location;
@@ -203,7 +206,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +import org.bukkit.util.Vector;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Common interface for {@link FinePosition} and {@link BlockPosition}.
@@ -211,6 +214,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 + * <b>May see breaking changes until Experimental annotation is removed.</b>
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public interface Position {
 +
 +    FinePosition FINE_ZERO = new FinePositionImpl(0, 0, 0);
@@ -287,7 +291,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @param z z value to offset
 +     * @return the offset position
 +     */
-+    @NotNull Position offset(int x, int y, int z);
++    Position offset(int x, int y, int z);
 +
 +    /**
 +     * Returns a position offset by the specified amounts.
@@ -297,7 +301,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @param z z value to offset
 +     * @return the offset position
 +     */
-+    @NotNull FinePosition offset(double x, double y, double z);
++    FinePosition offset(double x, double y, double z);
 +
 +    /**
 +     * Returns a new position at the center of the block position this represents
@@ -305,7 +309,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @return a new center position
 +     */
 +    @Contract(value = "-> new", pure = true)
-+    default @NotNull FinePosition toCenter() {
++    default FinePosition toCenter() {
 +        return new FinePositionImpl(this.blockX() + 0.5, this.blockY() + 0.5, this.blockZ() + 0.5);
 +    }
 +
@@ -316,7 +320,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @return the block position
 +     */
 +    @Contract(pure = true)
-+    @NotNull BlockPosition toBlock();
++    BlockPosition toBlock();
 +
 +    /**
 +     * Converts this position to a vector
@@ -324,7 +328,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @return a new vector
 +     */
 +    @Contract(value = "-> new", pure = true)
-+    default @NotNull Vector toVector() {
++    default Vector toVector() {
 +        return new Vector(this.x(), this.y(), this.z());
 +    }
 +
@@ -335,7 +339,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @return a new location
 +     */
 +    @Contract(value = "_ -> new", pure = true)
-+    default @NotNull Location toLocation(@NotNull World world) {
++    default Location toLocation(final World world) {
 +        return new Location(world, this.x(), this.y(), this.z());
 +    }
 +
@@ -348,7 +352,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @return a position with those coords
 +     */
 +    @Contract(value = "_, _, _ -> new", pure = true)
-+    static @NotNull BlockPosition block(int x, int y, int z) {
++    static BlockPosition block(final int x, final int y, final int z) {
 +        return new BlockPositionImpl(x, y, z);
 +    }
 +
@@ -359,7 +363,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @return a new position at that location
 +     */
 +    @Contract(value = "_ -> new", pure = true)
-+    static @NotNull BlockPosition block(@NotNull Location location) {
++    static BlockPosition block(final Location location) {
 +        return new BlockPositionImpl(location.getBlockX(), location.getBlockY(), location.getBlockZ());
 +    }
 +
@@ -372,7 +376,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @return a position with those coords
 +     */
 +    @Contract(value = "_, _, _ -> new", pure = true)
-+    static @NotNull FinePosition fine(double x, double y, double z) {
++    static FinePosition fine(final double x, final double y, final double z) {
 +        return new FinePositionImpl(x, y, z);
 +    }
 +
@@ -383,7 +387,7 @@ index 0000000000000000000000000000000000000000..26bc5a0fa67855af87c8fd4cd8229b4d
 +     * @return a new position at that location
 +     */
 +    @Contract(value = "_ -> new", pure = true)
-+    static @NotNull FinePosition fine(@NotNull Location location) {
++    static FinePosition fine(final Location location) {
 +        return new FinePositionImpl(location.getX(), location.getY(), location.getZ());
 +    }
 +}
diff --git a/patches/api/0015-Expose-server-build-information.patch b/patches/api/0015-Expose-server-build-information.patch
index 3f8bdaf317..f1bf77caf8 100644
--- a/patches/api/0015-Expose-server-build-information.patch
+++ b/patches/api/0015-Expose-server-build-information.patch
@@ -63,10 +63,10 @@ index 0000000000000000000000000000000000000000..023cc52a9e28e1238c7452c0f3f577f2
 +}
 diff --git a/src/main/java/io/papermc/paper/ServerBuildInfo.java b/src/main/java/io/papermc/paper/ServerBuildInfo.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..9df9d09aa477d4cd3c496ba0933c816df1ef0964
+index 0000000000000000000000000000000000000000..652ff54e7c50412503725d628bfe72ed03059790
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/ServerBuildInfo.java
-@@ -0,0 +1,121 @@
+@@ -0,0 +1,122 @@
 +package io.papermc.paper;
 +
 +import java.time.Instant;
@@ -75,11 +75,12 @@ index 0000000000000000000000000000000000000000..9df9d09aa477d4cd3c496ba0933c816d
 +import net.kyori.adventure.key.Key;
 +import net.kyori.adventure.util.Services;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Information about the current server build.
 + */
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface ServerBuildInfo {
 +    /**
@@ -92,7 +93,7 @@ index 0000000000000000000000000000000000000000..9df9d09aa477d4cd3c496ba0933c816d
 +     *
 +     * @return the {@code ServerBuildInfo}
 +     */
-+    static @NotNull ServerBuildInfo buildInfo() {
++    static ServerBuildInfo buildInfo() {
 +        //<editor-fold defaultstate="collapsed" desc="Holder">
 +        final class Holder {
 +            static final Optional<ServerBuildInfo> INSTANCE = Services.service(ServerBuildInfo.class);
@@ -106,7 +107,7 @@ index 0000000000000000000000000000000000000000..9df9d09aa477d4cd3c496ba0933c816d
 +     *
 +     * @return the brand id of the server (e.g. "papermc:paper")
 +     */
-+    @NotNull Key brandId();
++    Key brandId();
 +
 +    /**
 +     * Checks if the current server supports the specified brand.
@@ -115,56 +116,56 @@ index 0000000000000000000000000000000000000000..9df9d09aa477d4cd3c496ba0933c816d
 +     * @return {@code true} if the server supports the specified brand
 +     */
 +    @ApiStatus.Experimental
-+    boolean isBrandCompatible(final @NotNull Key brandId);
++    boolean isBrandCompatible(final Key brandId);
 +
 +    /**
 +     * Gets the brand name of the server.
 +     *
 +     * @return the brand name of the server (e.g. "Paper")
 +     */
-+    @NotNull String brandName();
++    String brandName();
 +
 +    /**
 +     * Gets the Minecraft version id.
 +     *
 +     * @return the Minecraft version id (e.g. "1.20.4", "1.20.2-pre2", "23w31a")
 +     */
-+    @NotNull String minecraftVersionId();
++    String minecraftVersionId();
 +
 +    /**
 +     * Gets the Minecraft version name.
 +     *
 +     * @return the Minecraft version name (e.g. "1.20.4", "1.20.2 Pre-release 2", "23w31a")
 +     */
-+    @NotNull String minecraftVersionName();
++    String minecraftVersionName();
 +
 +    /**
 +     * Gets the build number.
 +     *
 +     * @return the build number
 +     */
-+    @NotNull OptionalInt buildNumber();
++    OptionalInt buildNumber();
 +
 +    /**
 +     * Gets the build time.
 +     *
 +     * @return the build time
 +     */
-+    @NotNull Instant buildTime();
++    Instant buildTime();
 +
 +    /**
 +     * Gets the git commit branch.
 +     *
 +     * @return the git commit branch
 +     */
-+    @NotNull Optional<String> gitBranch();
++    Optional<String> gitBranch();
 +
 +    /**
 +     * Gets the git commit hash.
 +     *
 +     * @return the git commit hash
 +     */
-+    @NotNull Optional<String> gitCommit();
++    Optional<String> gitCommit();
 +
 +    /**
 +     * Creates a string representation of the server build information.
@@ -172,7 +173,7 @@ index 0000000000000000000000000000000000000000..9df9d09aa477d4cd3c496ba0933c816d
 +     * @param representation the type of representation
 +     * @return a string
 +     */
-+    @NotNull String asString(final @NotNull StringRepresentation representation);
++    String asString(final StringRepresentation representation);
 +
 +    /**
 +     * String representation types.
@@ -190,10 +191,10 @@ index 0000000000000000000000000000000000000000..9df9d09aa477d4cd3c496ba0933c816d
 +}
 diff --git a/src/main/java/io/papermc/paper/util/JarManifests.java b/src/main/java/io/papermc/paper/util/JarManifests.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..909617079db61b675cc7b60b44ef96b306076343
+index 0000000000000000000000000000000000000000..7915a70d676b1205dcae39259f670af258a1ab9b
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/util/JarManifests.java
-@@ -0,0 +1,37 @@
+@@ -0,0 +1,38 @@
 +package io.papermc.paper.util;
 +
 +import java.io.IOException;
@@ -204,9 +205,10 @@ index 0000000000000000000000000000000000000000..909617079db61b675cc7b60b44ef96b3
 +import java.util.WeakHashMap;
 +import java.util.jar.Manifest;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
++@NullMarked
 +@ApiStatus.Internal
 +public final class JarManifests {
 +    private JarManifests() {
@@ -214,7 +216,7 @@ index 0000000000000000000000000000000000000000..909617079db61b675cc7b60b44ef96b3
 +
 +    private static final Map<ClassLoader, Manifest> MANIFESTS = Collections.synchronizedMap(new WeakHashMap<>());
 +
-+    public static @Nullable Manifest manifest(final @NotNull Class<?> clazz) {
++    public static @Nullable Manifest manifest(final Class<?> clazz) {
 +        return MANIFESTS.computeIfAbsent(clazz.getClassLoader(), classLoader -> {
 +            final String classLocation = "/" + clazz.getName().replace(".", "/") + ".class";
 +            final URL resource = clazz.getResource(classLocation);
diff --git a/patches/api/0039-LootTable-API.patch b/patches/api/0039-LootTable-API.patch
index 40be416e93..366e828564 100644
--- a/patches/api/0039-LootTable-API.patch
+++ b/patches/api/0039-LootTable-API.patch
@@ -12,14 +12,13 @@ Provides methods to determine players looted state for an object
 
 diff --git a/src/main/java/com/destroystokyo/paper/loottable/LootableBlockInventory.java b/src/main/java/com/destroystokyo/paper/loottable/LootableBlockInventory.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..08e82b9de34c5ce8c5e83631b1229e90e5aa9694
+index 0000000000000000000000000000000000000000..6a03252d66a3e13c1960568ea23f6dcc673f34af
 --- /dev/null
 +++ b/src/main/java/com/destroystokyo/paper/loottable/LootableBlockInventory.java
-@@ -0,0 +1,18 @@
+@@ -0,0 +1,17 @@
 +package com.destroystokyo.paper.loottable;
 +
 +import org.bukkit.block.Block;
-+import org.jetbrains.annotations.NotNull;
 +import org.jspecify.annotations.NullMarked;
 +
 +/**
@@ -36,14 +35,13 @@ index 0000000000000000000000000000000000000000..08e82b9de34c5ce8c5e83631b1229e90
 +}
 diff --git a/src/main/java/com/destroystokyo/paper/loottable/LootableEntityInventory.java b/src/main/java/com/destroystokyo/paper/loottable/LootableEntityInventory.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..a1e1a0256010f293e7dfa63c6622e9125eb4cc73
+index 0000000000000000000000000000000000000000..31ca54dea65dc0363a0ff7991ba5be3b06533876
 --- /dev/null
 +++ b/src/main/java/com/destroystokyo/paper/loottable/LootableEntityInventory.java
-@@ -0,0 +1,18 @@
+@@ -0,0 +1,17 @@
 +package com.destroystokyo.paper.loottable;
 +
 +import org.bukkit.entity.Entity;
-+import org.jetbrains.annotations.NotNull;
 +import org.jspecify.annotations.NullMarked;
 +
 +/**
@@ -60,17 +58,17 @@ index 0000000000000000000000000000000000000000..a1e1a0256010f293e7dfa63c6622e912
 +}
 diff --git a/src/main/java/com/destroystokyo/paper/loottable/LootableInventory.java b/src/main/java/com/destroystokyo/paper/loottable/LootableInventory.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..b085e1217838012e4f4c6bcce100d8282190cdbc
+index 0000000000000000000000000000000000000000..9fb621200fb3969e8e440341e906acc3547b4039
 --- /dev/null
 +++ b/src/main/java/com/destroystokyo/paper/loottable/LootableInventory.java
-@@ -0,0 +1,129 @@
+@@ -0,0 +1,128 @@
 +package com.destroystokyo.paper.loottable;
 +
 +import java.util.UUID;
 +import org.bukkit.entity.Player;
 +import org.bukkit.loot.Lootable;
-+import org.jetbrains.annotations.Nullable;
 +import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Represents an Inventory that contains a Loot Table associated to it that will
@@ -141,8 +139,7 @@ index 0000000000000000000000000000000000000000..b085e1217838012e4f4c6bcce100d828
 +     * @param player The player to check
 +     * @return Timestamp last looted, or null if player has not looted this object
 +     */
-+    @Nullable
-+    Long getLastLooted(UUID player);
++    @Nullable Long getLastLooted(UUID player);
 +
 +    /**
 +     * Change the state of whether a player has looted this block
diff --git a/patches/api/0041-Misc-Utils.patch b/patches/api/0041-Misc-Utils.patch
index fac858b16c..3b0d9dbfd7 100644
--- a/patches/api/0041-Misc-Utils.patch
+++ b/patches/api/0041-Misc-Utils.patch
@@ -6,41 +6,44 @@ Subject: [PATCH] Misc Utils
 
 diff --git a/src/main/java/com/destroystokyo/paper/utils/CachedSizeConcurrentLinkedQueue.java b/src/main/java/com/destroystokyo/paper/utils/CachedSizeConcurrentLinkedQueue.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..5bb677ce585b856b3d3e589e29786a29619c56a7
+index 0000000000000000000000000000000000000000..ebaa12ecacd169f00e184fed95720d047eda8b9d
 --- /dev/null
 +++ b/src/main/java/com/destroystokyo/paper/utils/CachedSizeConcurrentLinkedQueue.java
-@@ -0,0 +1,34 @@
+@@ -0,0 +1,37 @@
 +package com.destroystokyo.paper.utils;
 +
 +import java.util.concurrent.ConcurrentLinkedQueue;
 +import java.util.concurrent.atomic.LongAdder;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
++@NullMarked
++@ApiStatus.Internal
 +public class CachedSizeConcurrentLinkedQueue<E> extends ConcurrentLinkedQueue<E> {
++
 +    private final LongAdder cachedSize = new LongAdder();
 +
 +    @Override
-+    public boolean add(@NotNull E e) {
-+        boolean result = super.add(e);
++    public boolean add(final E e) {
++        final boolean result = super.add(e);
 +        if (result) {
-+            cachedSize.increment();
++            this.cachedSize.increment();
 +        }
 +        return result;
 +    }
 +
-+    @Nullable
 +    @Override
-+    public E poll() {
-+        E result = super.poll();
++    public @Nullable E poll() {
++        final E result = super.poll();
 +        if (result != null) {
-+            cachedSize.decrement();
++            this.cachedSize.decrement();
 +        }
 +        return result;
 +    }
 +
 +    @Override
 +    public int size() {
-+        return cachedSize.intValue();
++        return this.cachedSize.intValue();
 +    }
 +}
diff --git a/patches/api/0055-PlayerAttemptPickupItemEvent.patch b/patches/api/0055-PlayerAttemptPickupItemEvent.patch
index e688f92976..b6059f5757 100644
--- a/patches/api/0055-PlayerAttemptPickupItemEvent.patch
+++ b/patches/api/0055-PlayerAttemptPickupItemEvent.patch
@@ -6,10 +6,10 @@ Subject: [PATCH] PlayerAttemptPickupItemEvent
 
 diff --git a/src/main/java/org/bukkit/event/player/PlayerAttemptPickupItemEvent.java b/src/main/java/org/bukkit/event/player/PlayerAttemptPickupItemEvent.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..13e4b1309ea9965a07fc8b276d5a7e606e205824
+index 0000000000000000000000000000000000000000..eff29875f6282d8bd04a33cb572c90090742d3b2
 --- /dev/null
 +++ b/src/main/java/org/bukkit/event/player/PlayerAttemptPickupItemEvent.java
-@@ -0,0 +1,96 @@
+@@ -0,0 +1,94 @@
 +package org.bukkit.event.player;
 +
 +import org.bukkit.entity.Item;
@@ -17,16 +17,17 @@ index 0000000000000000000000000000000000000000..13e4b1309ea9965a07fc8b276d5a7e60
 +import org.bukkit.event.Cancellable;
 +import org.bukkit.event.HandlerList;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Thrown when a player attempts to pick an item up from the ground
 + */
++@NullMarked
 +public class PlayerAttemptPickupItemEvent extends PlayerEvent implements Cancellable {
 +
 +    private static final HandlerList HANDLER_LIST = new HandlerList();
 +
-+    @NotNull private final Item item;
++    private final Item item;
 +    private final int remaining;
 +    private boolean flyAtPlayer = true;
 +
@@ -34,12 +35,12 @@ index 0000000000000000000000000000000000000000..13e4b1309ea9965a07fc8b276d5a7e60
 +
 +    @Deprecated // Remove in 1.13 // Remove in 1.14?
 +    @ApiStatus.Internal
-+    public PlayerAttemptPickupItemEvent(@NotNull final Player player, @NotNull final Item item) {
++    public PlayerAttemptPickupItemEvent(final Player player, final Item item) {
 +        this(player, item, 0);
 +    }
 +
 +    @ApiStatus.Internal
-+    public PlayerAttemptPickupItemEvent(@NotNull final Player player, @NotNull final Item item, final int remaining) {
++    public PlayerAttemptPickupItemEvent(final Player player, final Item item, final int remaining) {
 +        super(player);
 +        this.item = item;
 +        this.remaining = remaining;
@@ -50,7 +51,6 @@ index 0000000000000000000000000000000000000000..13e4b1309ea9965a07fc8b276d5a7e60
 +     *
 +     * @return Item
 +     */
-+    @NotNull
 +    public Item getItem() {
 +        return this.item;
 +    }
@@ -95,13 +95,11 @@ index 0000000000000000000000000000000000000000..13e4b1309ea9965a07fc8b276d5a7e60
 +        this.flyAtPlayer = !cancel;
 +    }
 +
-+    @NotNull
 +    @Override
 +    public HandlerList getHandlers() {
 +        return HANDLER_LIST;
 +    }
 +
-+    @NotNull
 +    public static HandlerList getHandlerList() {
 +        return HANDLER_LIST;
 +    }
diff --git a/patches/api/0056-Add-UnknownCommandEvent.patch b/patches/api/0056-Add-UnknownCommandEvent.patch
index fb53ee7d60..8c7d30f48d 100644
--- a/patches/api/0056-Add-UnknownCommandEvent.patch
+++ b/patches/api/0056-Add-UnknownCommandEvent.patch
@@ -6,10 +6,10 @@ Subject: [PATCH] Add UnknownCommandEvent
 
 diff --git a/src/main/java/org/bukkit/event/command/UnknownCommandEvent.java b/src/main/java/org/bukkit/event/command/UnknownCommandEvent.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..9bdeeecdb6021d61fd9141270011e56b06a58a76
+index 0000000000000000000000000000000000000000..58fe8f60ad5e7ca0ffddebb7ba5748bbfb129ddd
 --- /dev/null
 +++ b/src/main/java/org/bukkit/event/command/UnknownCommandEvent.java
-@@ -0,0 +1,110 @@
+@@ -0,0 +1,105 @@
 +package org.bukkit.event.command;
 +
 +import net.kyori.adventure.text.Component;
@@ -19,22 +19,23 @@ index 0000000000000000000000000000000000000000..9bdeeecdb6021d61fd9141270011e56b
 +import org.bukkit.event.HandlerList;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Thrown when a player executes a command that is not defined
 + */
++@NullMarked
 +public class UnknownCommandEvent extends Event {
 +
 +    private static final HandlerList HANDLER_LIST = new HandlerList();
 +
-+    @NotNull private final CommandSender sender;
-+    @NotNull private final String commandLine;
-+    @Nullable private Component message;
++    private final CommandSender sender;
++    private final String commandLine;
++    private @Nullable Component message;
 +
 +    @ApiStatus.Internal
-+    public UnknownCommandEvent(@NotNull final CommandSender sender, @NotNull final String commandLine, @Nullable final Component message) {
++    public UnknownCommandEvent(final CommandSender sender, final String commandLine, final @Nullable Component message) {
 +        super(false);
 +        this.sender = sender;
 +        this.commandLine = commandLine;
@@ -46,7 +47,6 @@ index 0000000000000000000000000000000000000000..9bdeeecdb6021d61fd9141270011e56b
 +     *
 +     * @return Sender of the command
 +     */
-+    @NotNull
 +    public CommandSender getSender() {
 +        return this.sender;
 +    }
@@ -56,7 +56,6 @@ index 0000000000000000000000000000000000000000..9bdeeecdb6021d61fd9141270011e56b
 +     *
 +     * @return Command sent
 +     */
-+    @NotNull
 +    public String getCommandLine() {
 +        return this.commandLine;
 +    }
@@ -67,9 +66,8 @@ index 0000000000000000000000000000000000000000..9bdeeecdb6021d61fd9141270011e56b
 +     * @return Unknown command message
 +     * @deprecated use {@link #message()}
 +     */
-+    @Nullable
 +    @Deprecated
-+    public String getMessage() {
++    public @Nullable String getMessage() {
 +        return this.message == null ? null : LegacyComponentSerializer.legacySection().serialize(this.message);
 +    }
 +
@@ -91,9 +89,8 @@ index 0000000000000000000000000000000000000000..9bdeeecdb6021d61fd9141270011e56b
 +     *
 +     * @return Unknown command message
 +     */
-+    @Nullable
 +    @Contract(pure = true)
-+    public Component message() {
++    public @Nullable Component message() {
 +        return this.message;
 +    }
 +
@@ -108,13 +105,11 @@ index 0000000000000000000000000000000000000000..9bdeeecdb6021d61fd9141270011e56b
 +        this.message = message;
 +    }
 +
-+    @NotNull
 +    @Override
 +    public HandlerList getHandlers() {
 +        return HANDLER_LIST;
 +    }
 +
-+    @NotNull
 +    public static HandlerList getHandlerList() {
 +        return HANDLER_LIST;
 +    }
diff --git a/patches/api/0057-Basic-PlayerProfile-API.patch b/patches/api/0057-Basic-PlayerProfile-API.patch
index 1e069d46b5..3f09fa9187 100644
--- a/patches/api/0057-Basic-PlayerProfile-API.patch
+++ b/patches/api/0057-Basic-PlayerProfile-API.patch
@@ -7,29 +7,30 @@ Provides basic elements of a PlayerProfile to be used by future API/events
 
 diff --git a/src/main/java/com/destroystokyo/paper/profile/PlayerProfile.java b/src/main/java/com/destroystokyo/paper/profile/PlayerProfile.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c274a1ec4cd
+index 0000000000000000000000000000000000000000..324c1cba46c9eef95cc22ffa231b04f9298a5e00
 --- /dev/null
 +++ b/src/main/java/com/destroystokyo/paper/profile/PlayerProfile.java
-@@ -0,0 +1,234 @@
+@@ -0,0 +1,246 @@
 +package com.destroystokyo.paper.profile;
 +
 +import java.util.Collection;
 +import java.util.Set;
 +import java.util.UUID;
-+
 +import java.util.concurrent.CompletableFuture;
 +import org.bukkit.profile.PlayerTextures;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Represents a players profile for the game, such as UUID, Name, and textures.
 + */
++@NullMarked
 +public interface PlayerProfile extends org.bukkit.profile.PlayerProfile {
 +
 +    /**
 +     * @return The players name, if set
 +     */
++    @Override
 +    @Nullable
 +    String getName();
 +
@@ -39,14 +40,14 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +     * @param name The new Name
 +     * @return The previous Name
 +     */
-+    @NotNull
 +    @Deprecated(forRemoval = true, since = "1.18.1")
 +    String setName(@Nullable String name);
 +
 +    /**
 +     * @return The players unique identifier, if set
 +     */
-+    @Nullable UUID getId();
++    @Nullable
++    UUID getId();
 +
 +    /**
 +     * Sets this profiles UUID
@@ -54,8 +55,8 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +     * @param uuid The new UUID
 +     * @return The previous UUID
 +     */
-+    @Nullable
 +    @Deprecated(forRemoval = true, since = "1.18.1")
++    @Nullable
 +    UUID setId(@Nullable UUID uuid);
 +
 +    /**
@@ -65,7 +66,7 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +     *
 +     * @return the textures, not <code>null</code>
 +     */
-+    @NotNull
++    @Override
 +    PlayerTextures getTextures();
 +
 +    /**
@@ -74,16 +75,18 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +     * @param textures the textures to copy, or <code>null</code> to clear the
 +     * textures
 +     */
++    @Override
 +    void setTextures(@Nullable PlayerTextures textures);
 +
 +    /**
 +     * @return A Mutable set of this players properties, such as textures.
 +     * Values specified here are subject to implementation details.
 +     */
-+    @NotNull Set<ProfileProperty> getProperties();
++    Set<ProfileProperty> getProperties();
 +
 +    /**
 +     * Check if the Profile has the specified property
++     *
 +     * @param property Property name to check
 +     * @return If the property is set
 +     */
@@ -95,17 +98,19 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +     * @param property Property to set.
 +     * @throws IllegalArgumentException if setting the property results in more than 16 properties
 +     */
-+    void setProperty(@NotNull ProfileProperty property);
++    void setProperty(ProfileProperty property);
 +
 +    /**
 +     * Sets multiple properties. If any of the set properties already exist, it will be replaced
++     *
 +     * @param properties The properties to set
 +     * @throws IllegalArgumentException if the number of properties exceeds 16
 +     */
-+    void setProperties(@NotNull Collection<ProfileProperty> properties);
++    void setProperties(Collection<ProfileProperty> properties);
 +
 +    /**
 +     * Removes a specific property from this profile
++     *
 +     * @param property The property to remove
 +     * @return If a property was removed
 +     */
@@ -113,22 +118,24 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +
 +    /**
 +     * Removes a specific property from this profile
++     *
 +     * @param property The property to remove
 +     * @return If a property was removed
 +     */
-+    default boolean removeProperty(@NotNull ProfileProperty property) {
-+        return removeProperty(property.getName());
++    default boolean removeProperty(final ProfileProperty property) {
++        return this.removeProperty(property.getName());
 +    }
 +
 +    /**
 +     * Removes all properties in the collection
++     *
 +     * @param properties The properties to remove
 +     * @return If any property was removed
 +     */
-+    default boolean removeProperties(@NotNull Collection<ProfileProperty> properties) {
++    default boolean removeProperties(final Collection<ProfileProperty> properties) {
 +        boolean removed = false;
-+        for (ProfileProperty property : properties) {
-+            if (removeProperty(property)) {
++        for (final ProfileProperty property : properties) {
++            if (this.removeProperty(property)) {
 +                removed = true;
 +            }
 +        }
@@ -143,6 +150,7 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +    /**
 +     * @return If the profile is now complete (has UUID and Name)
 +     */
++    @Override
 +    boolean isComplete();
 +
 +    /**
@@ -175,21 +183,23 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +    /**
 +     * If this profile is not complete, then make the API call to complete it.
 +     * This is a blocking operation and should be done asynchronously.
-+     *
++     * <p>
 +     * This will also complete textures. If you do not want to load textures, use {{@link #complete(boolean)}}
++     *
 +     * @return If the profile is now complete (has UUID and Name) (if you get rate limited, this operation may fail)
 +     */
 +    default boolean complete() {
-+        return complete(true);
++        return this.complete(true);
 +    }
 +
 +    /**
 +     * If this profile is not complete, then make the API call to complete it.
 +     * This is a blocking operation and should be done asynchronously.
-+     *
++     * <p>
 +     * Optionally will also fill textures.
-+     *
++     * <p>
 +     * Online mode will be automatically determined
++     *
 +     * @param textures controls if we should fill the profile with texture properties
 +     * @return If the profile is now complete (has UUID and Name) (if you get rate limited, this operation may fail)
 +     */
@@ -198,8 +208,9 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +    /**
 +     * If this profile is not complete, then make the API call to complete it.
 +     * This is a blocking operation and should be done asynchronously.
-+     *
++     * <p>
 +     * Optionally will also fill textures.
++     *
 +     * @param textures controls if we should fill the profile with texture properties
 +     * @param onlineMode Treat this server as online mode or not
 +     * @return If the profile is now complete (has UUID and Name) (if you get rate limited, this operation may fail)
@@ -235,43 +246,45 @@ index 0000000000000000000000000000000000000000..b4f9ffbebab8eef99dbd81c816c16c27
 +     * </pre>
 +     */
 +    @Override
-+    @NotNull CompletableFuture<PlayerProfile> update();
++    CompletableFuture<PlayerProfile> update();
 +
 +    /**
 +     * Whether this Profile has textures associated to it
++     *
 +     * @return If it has a textures property
 +     */
 +    default boolean hasTextures() {
-+        return hasProperty("textures");
++        return this.hasProperty("textures");
 +    }
 +}
 diff --git a/src/main/java/com/destroystokyo/paper/profile/ProfileProperty.java b/src/main/java/com/destroystokyo/paper/profile/ProfileProperty.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..8f6240484d12f01bb555972feb0937bc74399a64
+index 0000000000000000000000000000000000000000..35341d8f1ac2d80f339084ef80d099a545027554
 --- /dev/null
 +++ b/src/main/java/com/destroystokyo/paper/profile/ProfileProperty.java
-@@ -0,0 +1,75 @@
+@@ -0,0 +1,73 @@
 +package com.destroystokyo.paper.profile;
 +
 +import com.google.common.base.Preconditions;
-+
 +import java.util.Objects;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Represents a property on a {@link PlayerProfile}
 + */
++@NullMarked
 +public final class ProfileProperty {
++
 +    private final String name;
 +    private final String value;
-+    private final String signature;
++    private final @Nullable String signature;
 +
-+    public ProfileProperty(@NotNull String name, @NotNull String value) {
++    public ProfileProperty(final String name, final String value) {
 +        this(name, value, null);
 +    }
 +
-+    public ProfileProperty(@NotNull String name, @NotNull String value, @Nullable String signature) {
++    public ProfileProperty(final String name, final String value, final @Nullable String signature) {
 +        this.name = Preconditions.checkNotNull(name, "ProfileProperty name can not be null");
 +        this.value = Preconditions.checkNotNull(value, "ProfileProperty value can not be null");
 +        this.signature = signature;
@@ -283,25 +296,22 @@ index 0000000000000000000000000000000000000000..8f6240484d12f01bb555972feb0937bc
 +    /**
 +     * @return The property name, ie "textures"
 +     */
-+    @NotNull
 +    public String getName() {
-+        return name;
++        return this.name;
 +    }
 +
 +    /**
 +     * @return The property value, likely to be base64 encoded
 +     */
-+    @NotNull
 +    public String getValue() {
-+        return value;
++        return this.value;
 +    }
 +
 +    /**
 +     * @return A signature from Mojang for signed properties
 +     */
-+    @Nullable
-+    public String getSignature() {
-+        return signature;
++    public @Nullable String getSignature() {
++        return this.signature;
 +    }
 +
 +    /**
@@ -312,18 +322,18 @@ index 0000000000000000000000000000000000000000..8f6240484d12f01bb555972feb0937bc
 +    }
 +
 +    @Override
-+    public boolean equals(Object o) {
++    public boolean equals(final @Nullable Object o) {
 +        if (this == o) return true;
-+        if (o == null || getClass() != o.getClass()) return false;
-+        ProfileProperty that = (ProfileProperty) o;
-+        return Objects.equals(name, that.name) &&
-+                Objects.equals(value, that.value) &&
-+                Objects.equals(signature, that.signature);
++        if (o == null || this.getClass() != o.getClass()) return false;
++        final ProfileProperty that = (ProfileProperty) o;
++        return Objects.equals(this.name, that.name) &&
++            Objects.equals(this.value, that.value) &&
++            Objects.equals(this.signature, that.signature);
 +    }
 +
 +    @Override
 +    public int hashCode() {
-+        return Objects.hash(name);
++        return Objects.hash(this.name);
 +    }
 +}
 diff --git a/src/main/java/org/bukkit/Bukkit.java b/src/main/java/org/bukkit/Bukkit.java
diff --git a/patches/api/0062-Improve-the-Saddle-API-for-Horses.patch b/patches/api/0062-Improve-the-Saddle-API-for-Horses.patch
index 85814456bf..033f539a9b 100644
--- a/patches/api/0062-Improve-the-Saddle-API-for-Horses.patch
+++ b/patches/api/0062-Improve-the-Saddle-API-for-Horses.patch
@@ -8,14 +8,16 @@ and access their saddle state separately from an interface shared with Armor.
 
 diff --git a/src/main/java/org/bukkit/inventory/ArmoredHorseInventory.java b/src/main/java/org/bukkit/inventory/ArmoredHorseInventory.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..163ffe8ff76ded6265d865901d5110fb6a56950d
+index 0000000000000000000000000000000000000000..994f34ac2062c092c2b4e5ff364067482d19588c
 --- /dev/null
 +++ b/src/main/java/org/bukkit/inventory/ArmoredHorseInventory.java
-@@ -0,0 +1,21 @@
+@@ -0,0 +1,22 @@
 +package org.bukkit.inventory;
 +
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
++@NullMarked
 +public interface ArmoredHorseInventory extends AbstractHorseInventory {
 +
 +    /**
@@ -23,8 +25,7 @@ index 0000000000000000000000000000000000000000..163ffe8ff76ded6265d865901d5110fb
 +     *
 +     * @return the armor item
 +     */
-+    @Nullable
-+    ItemStack getArmor();
++    @Nullable ItemStack getArmor();
 +
 +    /**
 +     * Sets the item in the horse's armor slot.
@@ -74,10 +75,14 @@ index 2fa2c9d07ecbafaf2396d913af90f1f4d432b238..5ac1afb8a213fa0fe344db4730ecbc5d
       * Gets the item in the llama's decor slot.
 diff --git a/src/main/java/org/bukkit/inventory/SaddledHorseInventory.java b/src/main/java/org/bukkit/inventory/SaddledHorseInventory.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..7944f26a3e2a92601c3be0e55c00c39cc16cf177
+index 0000000000000000000000000000000000000000..0f508a8df87f1e23764152d00e02a3da5131f034
 --- /dev/null
 +++ b/src/main/java/org/bukkit/inventory/SaddledHorseInventory.java
-@@ -0,0 +1,3 @@
+@@ -0,0 +1,7 @@
 +package org.bukkit.inventory;
 +
-+public interface SaddledHorseInventory extends AbstractHorseInventory {}
++import org.jspecify.annotations.NullMarked;
++
++@NullMarked
++public interface SaddledHorseInventory extends AbstractHorseInventory {
++}
diff --git a/patches/api/0073-AsyncTabCompleteEvent.patch b/patches/api/0073-AsyncTabCompleteEvent.patch
index 2ad169a7c5..e78867039c 100644
--- a/patches/api/0073-AsyncTabCompleteEvent.patch
+++ b/patches/api/0073-AsyncTabCompleteEvent.patch
@@ -356,15 +356,12 @@ index 0000000000000000000000000000000000000000..0482ecf5b84ba8e0260679049f384f34
 +}
 diff --git a/src/main/java/io/papermc/paper/util/TransformingRandomAccessList.java b/src/main/java/io/papermc/paper/util/TransformingRandomAccessList.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..6f560a51277ccbd46a9142cfa057d276118c1c7b
+index 0000000000000000000000000000000000000000..488250fdcdc93ca1aba5042f63fb6286db518014
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/util/TransformingRandomAccessList.java
-@@ -0,0 +1,169 @@
+@@ -0,0 +1,172 @@
 +package io.papermc.paper.util;
 +
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.jetbrains.annotations.NotNull;
-+
 +import java.util.AbstractList;
 +import java.util.Iterator;
 +import java.util.List;
@@ -372,6 +369,8 @@ index 0000000000000000000000000000000000000000..6f560a51277ccbd46a9142cfa057d276
 +import java.util.RandomAccess;
 +import java.util.function.Function;
 +import java.util.function.Predicate;
++import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +import static com.google.common.base.Preconditions.checkNotNull;
 +
@@ -381,7 +380,10 @@ index 0000000000000000000000000000000000000000..6f560a51277ccbd46a9142cfa057d276
 + * @param <F> backing list element type
 + * @param <T> transformed list element type
 + */
++@NullMarked
++@ApiStatus.Internal
 +public final class TransformingRandomAccessList<F, T> extends AbstractList<T> implements RandomAccess {
++
 +    final List<F> fromList;
 +    final Function<? super F, ? extends T> toFunction;
 +    final Function<? super T, ? extends F> fromFunction;
@@ -389,14 +391,14 @@ index 0000000000000000000000000000000000000000..6f560a51277ccbd46a9142cfa057d276
 +    /**
 +     * Create a new {@link TransformingRandomAccessList}.
 +     *
-+     * @param fromList     backing list
-+     * @param toFunction   function mapping backing list element type to transformed list element type
++     * @param fromList backing list
++     * @param toFunction function mapping backing list element type to transformed list element type
 +     * @param fromFunction function mapping transformed list element type to backing list element type
 +     */
 +    public TransformingRandomAccessList(
-+        final @NonNull List<F> fromList,
-+        final @NonNull Function<? super F, ? extends T> toFunction,
-+        final @NonNull Function<? super T, ? extends F> fromFunction
++        final List<F> fromList,
++        final Function<? super F, ? extends T> toFunction,
++        final Function<? super T, ? extends F> fromFunction
 +    ) {
 +        this.fromList = checkNotNull(fromList);
 +        this.toFunction = checkNotNull(toFunction);
@@ -409,25 +411,25 @@ index 0000000000000000000000000000000000000000..6f560a51277ccbd46a9142cfa057d276
 +    }
 +
 +    @Override
-+    public T get(int index) {
++    public T get(final int index) {
 +        return this.toFunction.apply(this.fromList.get(index));
 +    }
 +
 +    @Override
-+    public @NotNull Iterator<T> iterator() {
++    public Iterator<T> iterator() {
 +        return this.listIterator();
 +    }
 +
 +    @Override
-+    public @NotNull ListIterator<T> listIterator(int index) {
-+        return new TransformedListIterator<F, T>(this.fromList.listIterator(index)) {
++    public ListIterator<T> listIterator(final int index) {
++        return new TransformedListIterator<>(this.fromList.listIterator(index)) {
 +            @Override
-+            T transform(F from) {
++            T transform(final F from) {
 +                return TransformingRandomAccessList.this.toFunction.apply(from);
 +            }
 +
 +            @Override
-+            F transformBack(T from) {
++            F transformBack(final T from) {
 +                return TransformingRandomAccessList.this.fromFunction.apply(from);
 +            }
 +        };
@@ -439,13 +441,13 @@ index 0000000000000000000000000000000000000000..6f560a51277ccbd46a9142cfa057d276
 +    }
 +
 +    @Override
-+    public boolean removeIf(Predicate<? super T> filter) {
++    public boolean removeIf(final Predicate<? super T> filter) {
 +        checkNotNull(filter);
 +        return this.fromList.removeIf(element -> filter.test(this.toFunction.apply(element)));
 +    }
 +
 +    @Override
-+    public T remove(int index) {
++    public T remove(final int index) {
 +        return this.toFunction.apply(this.fromList.remove(index));
 +    }
 +
@@ -455,19 +457,20 @@ index 0000000000000000000000000000000000000000..6f560a51277ccbd46a9142cfa057d276
 +    }
 +
 +    @Override
-+    public T set(int i, T t) {
++    public T set(final int i, final T t) {
 +        return this.toFunction.apply(this.fromList.set(i, this.fromFunction.apply(t)));
 +    }
 +
 +    @Override
-+    public void add(int i, T t) {
++    public void add(final int i, final T t) {
 +        this.fromList.add(i, this.fromFunction.apply(t));
 +    }
 +
-+    static abstract class TransformedListIterator<F, T> implements ListIterator<T>, Iterator<T> {
++    abstract static class TransformedListIterator<F, T> implements ListIterator<T>, Iterator<T> {
++
 +        final Iterator<F> backingIterator;
 +
-+        TransformedListIterator(ListIterator<F> backingIterator) {
++        TransformedListIterator(final ListIterator<F> backingIterator) {
 +            this.backingIterator = checkNotNull((Iterator<F>) backingIterator);
 +        }
 +
@@ -475,7 +478,7 @@ index 0000000000000000000000000000000000000000..6f560a51277ccbd46a9142cfa057d276
 +            return cast(this.backingIterator);
 +        }
 +
-+        static <A> ListIterator<A> cast(Iterator<A> iterator) {
++        static <A> ListIterator<A> cast(final Iterator<A> iterator) {
 +            return (ListIterator<A>) iterator;
 +        }
 +
@@ -500,12 +503,12 @@ index 0000000000000000000000000000000000000000..6f560a51277ccbd46a9142cfa057d276
 +        }
 +
 +        @Override
-+        public void set(T element) {
++        public void set(final T element) {
 +            this.backingIterator().set(this.transformBack(element));
 +        }
 +
 +        @Override
-+        public void add(T element) {
++        public void add(final T element) {
 +            this.backingIterator().add(this.transformBack(element));
 +        }
 +
diff --git a/patches/api/0126-Expand-ArmorStand-API.patch b/patches/api/0126-Expand-ArmorStand-API.patch
index 7df27326f1..1fd6df1628 100644
--- a/patches/api/0126-Expand-ArmorStand-API.patch
+++ b/patches/api/0126-Expand-ArmorStand-API.patch
@@ -12,18 +12,19 @@ Co-authored-by: SoSeDiK <mrsosedik@gmail.com>
 
 diff --git a/src/main/java/io/papermc/paper/math/Rotations.java b/src/main/java/io/papermc/paper/math/Rotations.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..0ac1618113699ac50b9c35294bf23fb9fb7cfbad
+index 0000000000000000000000000000000000000000..2a8e1aa29ab87c69a02f72615fbf1374714f54cf
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/math/Rotations.java
-@@ -0,0 +1,100 @@
+@@ -0,0 +1,101 @@
 +package io.papermc.paper.math;
 +
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Rotations is an immutable object that stores rotations
 + * in degrees on each axis (X, Y, Z).
 + */
++@NullMarked
 +public interface Rotations {
 +
 +    /**
@@ -39,7 +40,7 @@ index 0000000000000000000000000000000000000000..0ac1618113699ac50b9c35294bf23fb9
 +     * @param z the angle for the Z axis in degrees
 +     * @return Rotations instance holding the provided rotations
 +     */
-+    static @NotNull Rotations ofDegrees(double x, double y, double z) {
++    static Rotations ofDegrees(final double x, final double y, final double z) {
 +        return new RotationsImpl(x, y, z);
 +    }
 +
@@ -71,7 +72,7 @@ index 0000000000000000000000000000000000000000..0ac1618113699ac50b9c35294bf23fb9
 +     * @param x the angle in degrees
 +     * @return the resultant Rotations
 +     */
-+    @NotNull Rotations withX(double x);
++    Rotations withX(double x);
 +
 +    /**
 +     * Returns a new Rotations instance which is the result
@@ -80,7 +81,7 @@ index 0000000000000000000000000000000000000000..0ac1618113699ac50b9c35294bf23fb9
 +     * @param y the angle in degrees
 +     * @return the resultant Rotations
 +     */
-+    @NotNull Rotations withY(double y);
++    Rotations withY(double y);
 +
 +    /**
 +     * Returns a new Rotations instance which is the result
@@ -89,7 +90,7 @@ index 0000000000000000000000000000000000000000..0ac1618113699ac50b9c35294bf23fb9
 +     * @param z the angle in degrees
 +     * @return the resultant Rotations
 +     */
-+    @NotNull Rotations withZ(double z);
++    Rotations withZ(double z);
 +
 +    /**
 +     * Returns a new Rotations instance which is the result of adding
@@ -100,7 +101,7 @@ index 0000000000000000000000000000000000000000..0ac1618113699ac50b9c35294bf23fb9
 +     * @param z the angle to add to the Z axis in degrees
 +     * @return the resultant Rotations
 +     */
-+    @NotNull Rotations add(double x, double y, double z);
++    Rotations add(double x, double y, double z);
 +
 +    /**
 +     * Returns a new Rotations instance which is the result of subtracting
@@ -111,40 +112,41 @@ index 0000000000000000000000000000000000000000..0ac1618113699ac50b9c35294bf23fb9
 +     * @param z the angle to subtract from the Z axis in degrees
 +     * @return the resultant Rotations
 +     */
-+    default @NotNull Rotations subtract(double x, double y, double z) {
-+        return add(-x, -y, -z);
++    default Rotations subtract(final double x, final double y, final double z) {
++        return this.add(-x, -y, -z);
 +    }
 +
 +}
 diff --git a/src/main/java/io/papermc/paper/math/RotationsImpl.java b/src/main/java/io/papermc/paper/math/RotationsImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..53359ab4a6659bce895deef6a21cde848d3cadcd
+index 0000000000000000000000000000000000000000..35b493b870240f2cb142ea0c3bc2a5b2a89af25b
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/math/RotationsImpl.java
-@@ -0,0 +1,27 @@
+@@ -0,0 +1,28 @@
 +package io.papermc.paper.math;
 +
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
++@NullMarked
 +record RotationsImpl(double x, double y, double z) implements Rotations {
 +
 +    @Override
-+    public @NotNull RotationsImpl withX(double x) {
-+        return new RotationsImpl(x, y, z);
++    public RotationsImpl withX(final double x) {
++        return new RotationsImpl(x, this.y, this.z);
 +    }
 +
 +    @Override
-+    public @NotNull RotationsImpl withY(double y) {
-+        return new RotationsImpl(x, y, z);
++    public RotationsImpl withY(final double y) {
++        return new RotationsImpl(this.x, y, this.z);
 +    }
 +
 +    @Override
-+    public @NotNull RotationsImpl withZ(double z) {
-+        return new RotationsImpl(x, y, z);
++    public RotationsImpl withZ(final double z) {
++        return new RotationsImpl(this.x, this.y, z);
 +    }
 +
 +    @Override
-+    public @NotNull RotationsImpl add(double x, double y, double z) {
++    public RotationsImpl add(final double x, final double y, final double z) {
 +        return new RotationsImpl(this.x + x, this.y + y, this.z + z);
 +    }
 +
diff --git a/patches/api/0188-Add-villager-reputation-API.patch b/patches/api/0188-Add-villager-reputation-API.patch
index fc368610e2..4a5414e548 100644
--- a/patches/api/0188-Add-villager-reputation-API.patch
+++ b/patches/api/0188-Add-villager-reputation-API.patch
@@ -6,17 +6,15 @@ Subject: [PATCH] Add villager reputation API
 
 diff --git a/src/main/java/com/destroystokyo/paper/entity/villager/Reputation.java b/src/main/java/com/destroystokyo/paper/entity/villager/Reputation.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..f16294ef3148f8671389fa097e3e369a046e48cf
+index 0000000000000000000000000000000000000000..cbbf70507c2df922e75b686c36500f6f85f92db6
 --- /dev/null
 +++ b/src/main/java/com/destroystokyo/paper/entity/villager/Reputation.java
-@@ -0,0 +1,58 @@
+@@ -0,0 +1,56 @@
 +package com.destroystokyo.paper.entity.villager;
 +
 +import com.google.common.base.Preconditions;
-+
 +import java.util.EnumMap;
 +import java.util.Map;
-+import org.jetbrains.annotations.NotNull;
 +import org.jspecify.annotations.NullMarked;
 +
 +/**
@@ -31,7 +29,7 @@ index 0000000000000000000000000000000000000000..f16294ef3148f8671389fa097e3e369a
 +        this(new EnumMap<>(ReputationType.class));
 +    }
 +
-+    public Reputation(Map<ReputationType, Integer> reputation) {
++    public Reputation(final Map<ReputationType, Integer> reputation) {
 +        Preconditions.checkNotNull(reputation, "reputation cannot be null");
 +        this.reputation = reputation;
 +    }
@@ -42,7 +40,7 @@ index 0000000000000000000000000000000000000000..f16294ef3148f8671389fa097e3e369a
 +     * @param type The {@link ReputationType type} of reputation to get.
 +     * @return The value of the {@link ReputationType type}.
 +     */
-+    public int getReputation(ReputationType type) {
++    public int getReputation(final ReputationType type) {
 +        Preconditions.checkNotNull(type, "the reputation type cannot be null");
 +        return this.reputation.getOrDefault(type, 0);
 +    }
@@ -53,7 +51,7 @@ index 0000000000000000000000000000000000000000..f16294ef3148f8671389fa097e3e369a
 +     * @param type The {@link ReputationType type} of reputation to set.
 +     * @param value The value of the {@link ReputationType type}.
 +     */
-+    public void setReputation(ReputationType type, int value) {
++    public void setReputation(final ReputationType type, final int value) {
 +        Preconditions.checkNotNull(type, "the reputation type cannot be null");
 +        this.reputation.put(type, value);
 +    }
@@ -64,7 +62,7 @@ index 0000000000000000000000000000000000000000..f16294ef3148f8671389fa097e3e369a
 +     * @param type The {@link ReputationType type} to check
 +     * @return If there is a value for this {@link ReputationType type} set.
 +     */
-+    public boolean hasReputationSet(ReputationType type) {
++    public boolean hasReputationSet(final ReputationType type) {
 +        return this.reputation.containsKey(type);
 +    }
 +}
diff --git a/patches/api/0199-Add-moon-phase-API.patch b/patches/api/0199-Add-moon-phase-API.patch
index d949b274a6..bb0b1570be 100644
--- a/patches/api/0199-Add-moon-phase-API.patch
+++ b/patches/api/0199-Add-moon-phase-API.patch
@@ -6,17 +6,17 @@ Subject: [PATCH] Add moon phase API
 
 diff --git a/src/main/java/io/papermc/paper/world/MoonPhase.java b/src/main/java/io/papermc/paper/world/MoonPhase.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..df05153397b42930cd53d37b30824c7e5f008f7e
+index 0000000000000000000000000000000000000000..0b24e1a92bba4fed0ca2d4336a3b8351a800f93a
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/world/MoonPhase.java
-@@ -0,0 +1,36 @@
+@@ -0,0 +1,35 @@
 +package io.papermc.paper.world;
 +
-+import org.jetbrains.annotations.NotNull;
-+
 +import java.util.HashMap;
 +import java.util.Map;
++import org.jspecify.annotations.NullMarked;
 +
++@NullMarked
 +public enum MoonPhase {
 +    FULL_MOON(0L),
 +    WANING_GIBBOUS(1L),
@@ -29,20 +29,19 @@ index 0000000000000000000000000000000000000000..df05153397b42930cd53d37b30824c7e
 +
 +    private final long day;
 +
-+    MoonPhase(long day) {
++    MoonPhase(final long day) {
 +        this.day = day;
 +    }
 +
 +    private static final Map<Long, MoonPhase> BY_DAY = new HashMap<>();
 +
 +    static {
-+        for (MoonPhase phase : values()) {
++        for (final MoonPhase phase : values()) {
 +            BY_DAY.put(phase.day, phase);
 +        }
 +    }
 +
-+    @NotNull
-+    public static MoonPhase getPhase(long day) {
++    public static MoonPhase getPhase(final long day) {
 +        return BY_DAY.get(day % 8L);
 +    }
 +}
diff --git a/patches/api/0236-Add-RegistryAccess-for-managing-registries.patch b/patches/api/0236-Add-RegistryAccess-for-managing-registries.patch
index cce62703ab..f08dfa8fde 100644
--- a/patches/api/0236-Add-RegistryAccess-for-managing-registries.patch
+++ b/patches/api/0236-Add-RegistryAccess-for-managing-registries.patch
@@ -96,23 +96,24 @@ index 0000000000000000000000000000000000000000..f29e76a6b66ddfec12ddf8db6dcb2df6
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/RegistryAccess.java b/src/main/java/io/papermc/paper/registry/RegistryAccess.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..86ab67ff5023bf6adea80b02648b6f67476e30e5
+index 0000000000000000000000000000000000000000..00a3a4a196808b4b5c84ecccbfb1ea0e3825146a
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/RegistryAccess.java
-@@ -0,0 +1,49 @@
+@@ -0,0 +1,50 @@
 +package io.papermc.paper.registry;
 +
 +import org.bukkit.Keyed;
 +import org.bukkit.Registry;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Used for accessing different {@link Registry} instances
 + * by a {@link RegistryKey}. Get the main instance of {@link RegistryAccess}
 + * with {@link RegistryAccess#registryAccess()}.
 + */
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface RegistryAccess {
 +
@@ -121,7 +122,7 @@ index 0000000000000000000000000000000000000000..86ab67ff5023bf6adea80b02648b6f67
 +     *
 +     * @return the RegistryAccess instance
 +     */
-+    static @NotNull RegistryAccess registryAccess() {
++    static RegistryAccess registryAccess() {
 +        return RegistryAccessHolder.INSTANCE.orElseThrow(() -> new IllegalStateException("No RegistryAccess implementation found"));
 +    }
 +
@@ -134,7 +135,7 @@ index 0000000000000000000000000000000000000000..86ab67ff5023bf6adea80b02648b6f67
 +     * @deprecated use {@link #getRegistry(RegistryKey)} with keys from {@link RegistryKey}
 +     */
 +    @Deprecated(since = "1.20.6", forRemoval = true)
-+    <T extends Keyed> @Nullable Registry<T> getRegistry(@NotNull Class<T> type);
++    <T extends Keyed> @Nullable Registry<T> getRegistry(Class<T> type);
 +
 +    /**
 +     * Gets the registry with the specified key.
@@ -147,7 +148,7 @@ index 0000000000000000000000000000000000000000..86ab67ff5023bf6adea80b02648b6f67
 +     */
 +    // Future note: We should have no trouble removing this generic qualifier when
 +    // registry types no longer have to be "keyed" as it shouldn't break ABI or API.
-+    <T extends Keyed> @NotNull Registry<T> getRegistry(@NotNull RegistryKey<T> registryKey);
++    <T extends Keyed> Registry<T> getRegistry(RegistryKey<T> registryKey);
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/RegistryAccessHolder.java b/src/main/java/io/papermc/paper/registry/RegistryAccessHolder.java
 new file mode 100644
@@ -168,16 +169,16 @@ index 0000000000000000000000000000000000000000..b89e19c070f97c9662f1e16309446494
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/RegistryKeyImpl.java b/src/main/java/io/papermc/paper/registry/RegistryKeyImpl.java
-index 791813220b2504214b1adecc69093cd600fb0f8c..47fe5b0d5d031110c27210a0a256c260b35d9ba1 100644
+index 80e3e64f47ac55a4978c9e5b430e2f2d1c871d1b..ac68dfce754dc7e014bb31bba32d9b246ffd411c 100644
 --- a/src/main/java/io/papermc/paper/registry/RegistryKeyImpl.java
 +++ b/src/main/java/io/papermc/paper/registry/RegistryKeyImpl.java
-@@ -10,6 +10,17 @@ record RegistryKeyImpl<T>(@NotNull Key key) implements RegistryKey<T> {
+@@ -12,6 +12,17 @@ record RegistryKeyImpl<T>(Key key) implements RegistryKey<T> {
  
      static final Set<RegistryKey<?>> REGISTRY_KEYS = Sets.newIdentityHashSet();
  
 +    // override equals and hashCode to this can be used to simulate an "identity" hashmap
 +    @Override
-+    public boolean equals(final Object obj) {
++    public boolean equals(final @Nullable Object obj) {
 +        return obj == this;
 +    }
 +
diff --git a/patches/api/0270-Add-basic-Datapack-API.patch b/patches/api/0270-Add-basic-Datapack-API.patch
index 0aa103eff0..ee03cb3350 100644
--- a/patches/api/0270-Add-basic-Datapack-API.patch
+++ b/patches/api/0270-Add-basic-Datapack-API.patch
@@ -7,23 +7,24 @@ Co-authored-by: Jake Potrebic <jake.m.potrebic@gmail.com>
 
 diff --git a/src/main/java/io/papermc/paper/datapack/Datapack.java b/src/main/java/io/papermc/paper/datapack/Datapack.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..233a31afa9673c9cb8d9eb52551425ff15f79661
+index 0000000000000000000000000000000000000000..95039ec90f81993cb2e36f82b7d13e9e7a30220e
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/datapack/Datapack.java
-@@ -0,0 +1,98 @@
+@@ -0,0 +1,99 @@
 +package io.papermc.paper.datapack;
 +
 +import java.util.Set;
 +import net.kyori.adventure.text.Component;
 +import org.bukkit.FeatureFlag;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.Contract;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * This is a snapshot of a datapack on the server. It
 + * won't be updated as datapacks are updated.
 + */
++@NullMarked
 +public interface Datapack {
 +
 +    /**
@@ -32,21 +33,21 @@ index 0000000000000000000000000000000000000000..233a31afa9673c9cb8d9eb52551425ff
 +     * @return the name of the pack
 +     */
 +    @Contract(pure = true)
-+    @NonNull String getName();
++    String getName();
 +
 +    /**
 +     * Gets the title component of this datapack.
 +     *
 +     * @return the title
 +     */
-+    @NonNull Component getTitle();
++    Component getTitle();
 +
 +    /**
 +     * Gets the description component of this datapack.
 +     *
 +     * @return the description
 +     */
-+    @NonNull Component getDescription();
++    Component getDescription();
 +
 +    /**
 +     * Gets if this datapack is required to be enabled.
@@ -60,14 +61,14 @@ index 0000000000000000000000000000000000000000..233a31afa9673c9cb8d9eb52551425ff
 +     *
 +     * @return the compatibility of the pack
 +     */
-+    @NonNull Compatibility getCompatibility();
++    Compatibility getCompatibility();
 +
 +    /**
 +     * Gets the set of required features for this datapack.
 +     *
 +     * @return the set of required features
 +     */
-+    @NonNull @Unmodifiable Set<FeatureFlag> getRequiredFeatures();
++    @Unmodifiable Set<FeatureFlag> getRequiredFeatures();
 +
 +    /**
 +     * Gets the enabled state of this pack.
@@ -91,7 +92,7 @@ index 0000000000000000000000000000000000000000..233a31afa9673c9cb8d9eb52551425ff
 +     *
 +     * @return the pack source
 +     */
-+    @NonNull DatapackSource getSource();
++    DatapackSource getSource();
 +
 +    /**
 +     * Computes the component vanilla Minecraft uses
@@ -101,7 +102,7 @@ index 0000000000000000000000000000000000000000..233a31afa9673c9cb8d9eb52551425ff
 +     * @return a new component
 +     */
 +    @Contract(pure = true, value = "-> new")
-+    @NonNull Component computeDisplayName();
++    Component computeDisplayName();
 +
 +    enum Compatibility {
 +        TOO_OLD,
@@ -111,18 +112,18 @@ index 0000000000000000000000000000000000000000..233a31afa9673c9cb8d9eb52551425ff
 +}
 diff --git a/src/main/java/io/papermc/paper/datapack/DatapackManager.java b/src/main/java/io/papermc/paper/datapack/DatapackManager.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..bbb81a8058a67fd554c781dbb4908434ad339655
+index 0000000000000000000000000000000000000000..4f758a781612bb14c8f2ee41b2b6f40a074e6359
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/datapack/DatapackManager.java
 @@ -0,0 +1,43 @@
 +package io.papermc.paper.datapack;
 +
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+
 +import java.util.Collection;
-+import org.checkerframework.checker.nullness.qual.Nullable;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
++@NullMarked
 +public interface DatapackManager {
 +
 +    /**
@@ -140,7 +141,7 @@ index 0000000000000000000000000000000000000000..bbb81a8058a67fd554c781dbb4908434
 +     * @param name the name/id of the datapack
 +     * @return the datapack, or null if not found
 +     */
-+    @Nullable Datapack getPack(@NonNull String name);
++    @Nullable Datapack getPack(String name);
 +
 +    /**
 +     * Gets the available datapacks. May require calling {@link #refreshPacks()} before
@@ -148,7 +149,7 @@ index 0000000000000000000000000000000000000000..bbb81a8058a67fd554c781dbb4908434
 +     *
 +     * @return all the packs known to the server
 +     */
-+    @NonNull @Unmodifiable Collection<Datapack> getPacks();
++    @Unmodifiable Collection<Datapack> getPacks();
 +
 +    /**
 +     * Gets the enabled datapacks. May require calling {@link #refreshPacks()} before
@@ -156,19 +157,22 @@ index 0000000000000000000000000000000000000000..bbb81a8058a67fd554c781dbb4908434
 +     *
 +     * @return all the packs which are currently enabled
 +     */
-+    @NonNull @Unmodifiable Collection<Datapack> getEnabledPacks();
++    @Unmodifiable Collection<Datapack> getEnabledPacks();
 +}
 diff --git a/src/main/java/io/papermc/paper/datapack/DatapackSource.java b/src/main/java/io/papermc/paper/datapack/DatapackSource.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..1679cbd78920005475343092857e13906ab73f82
+index 0000000000000000000000000000000000000000..b9b81cd974c2df501fef55bd8d9b78406c073038
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/datapack/DatapackSource.java
-@@ -0,0 +1,17 @@
+@@ -0,0 +1,20 @@
 +package io.papermc.paper.datapack;
 +
++import org.jspecify.annotations.NullMarked;
++
 +/**
 + * Source of a datapack.
 + */
++@NullMarked
 +public sealed interface DatapackSource permits DatapackSourceImpl {
 +
 +    DatapackSource DEFAULT = create("default");
@@ -183,15 +187,17 @@ index 0000000000000000000000000000000000000000..1679cbd78920005475343092857e1390
 +}
 diff --git a/src/main/java/io/papermc/paper/datapack/DatapackSourceImpl.java b/src/main/java/io/papermc/paper/datapack/DatapackSourceImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..3eb4d1df8187fdeab74948d261d9c8e03e55605c
+index 0000000000000000000000000000000000000000..0dfd101f01d16cc38f21831ca873633453dc6c9e
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/datapack/DatapackSourceImpl.java
-@@ -0,0 +1,12 @@
+@@ -0,0 +1,14 @@
 +package io.papermc.paper.datapack;
 +
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
++@NullMarked
 +record DatapackSourceImpl(String name) implements DatapackSource {
 +
 +    @Override
diff --git a/patches/api/0287-Missing-Entity-API.patch b/patches/api/0287-Missing-Entity-API.patch
index 928fcd36a5..cb796c7184 100644
--- a/patches/api/0287-Missing-Entity-API.patch
+++ b/patches/api/0287-Missing-Entity-API.patch
@@ -16,19 +16,20 @@ Co-authored-by: TotalledZebra <Holappa57@gmail.com>
 
 diff --git a/src/main/java/io/papermc/paper/entity/SchoolableFish.java b/src/main/java/io/papermc/paper/entity/SchoolableFish.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..39ad7d283609d7e427a2ab35b6fad839e032fe92
+index 0000000000000000000000000000000000000000..a16329a8d08c74ce58960ff9dcc0af098b8543e9
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/entity/SchoolableFish.java
 @@ -0,0 +1,47 @@
 +package io.papermc.paper.entity;
 +
 +import org.bukkit.entity.Fish;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Represents a fish that can school with other fish.
 + */
++@NullMarked
 +public interface SchoolableFish extends Fish {
 +
 +    /**
@@ -36,7 +37,7 @@ index 0000000000000000000000000000000000000000..39ad7d283609d7e427a2ab35b6fad839
 +     *
 +     * @param leader fish to follow
 +     */
-+    void startFollowing(@NotNull SchoolableFish leader);
++    void startFollowing(SchoolableFish leader);
 +
 +    /**
 +     * Causes the fish to stop following their current
@@ -63,8 +64,7 @@ index 0000000000000000000000000000000000000000..39ad7d283609d7e427a2ab35b6fad839
 +     *
 +     * @return following fish
 +     */
-+    @Nullable
-+    SchoolableFish getSchoolLeader();
++    @Nullable SchoolableFish getSchoolLeader();
 +
 +}
 diff --git a/src/main/java/org/bukkit/entity/AbstractHorse.java b/src/main/java/org/bukkit/entity/AbstractHorse.java
diff --git a/patches/api/0300-More-CommandBlock-API.patch b/patches/api/0300-More-CommandBlock-API.patch
index c8c52c7587..077206eca6 100644
--- a/patches/api/0300-More-CommandBlock-API.patch
+++ b/patches/api/0300-More-CommandBlock-API.patch
@@ -6,16 +6,17 @@ Subject: [PATCH] More CommandBlock API
 
 diff --git a/src/main/java/io/papermc/paper/command/CommandBlockHolder.java b/src/main/java/io/papermc/paper/command/CommandBlockHolder.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..cbca0e890a8e79c98555c94fb6487e7d181901aa
+index 0000000000000000000000000000000000000000..8dc061e38a1728ec4d9dddcb3564ed1b1da746c8
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/CommandBlockHolder.java
-@@ -0,0 +1,58 @@
+@@ -0,0 +1,57 @@
 +package io.papermc.paper.command;
 +
 +import net.kyori.adventure.text.Component;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
++@NullMarked
 +public interface CommandBlockHolder {
 +
 +    /**
@@ -25,7 +26,6 @@ index 0000000000000000000000000000000000000000..cbca0e890a8e79c98555c94fb6487e7d
 +     *
 +     * @return Command that this CommandBlock will run when activated.
 +     */
-+    @NotNull
 +    String getCommand();
 +
 +    /**
@@ -42,7 +42,6 @@ index 0000000000000000000000000000000000000000..cbca0e890a8e79c98555c94fb6487e7d
 +     *
 +     * @return the last output
 +     */
-+    @NotNull
 +    Component lastOutput();
 +
 +    /**
diff --git a/patches/api/0307-Add-more-advancement-API.patch b/patches/api/0307-Add-more-advancement-API.patch
index 179dbdc225..6b17b3c11e 100644
--- a/patches/api/0307-Add-more-advancement-API.patch
+++ b/patches/api/0307-Add-more-advancement-API.patch
@@ -7,10 +7,10 @@ Co-authored-by: Jake Potrebic <jake.m.potrebic@gmail.com>
 
 diff --git a/src/main/java/io/papermc/paper/advancement/AdvancementDisplay.java b/src/main/java/io/papermc/paper/advancement/AdvancementDisplay.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d1336349590c
+index 0000000000000000000000000000000000000000..59228f2e66e982feca77d9f962004ceacb648783
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/advancement/AdvancementDisplay.java
-@@ -0,0 +1,166 @@
+@@ -0,0 +1,160 @@
 +package io.papermc.paper.advancement;
 +
 +import net.kyori.adventure.text.Component;
@@ -20,8 +20,8 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +import net.kyori.adventure.util.Index;
 +import org.bukkit.NamespacedKey;
 +import org.bukkit.inventory.ItemStack;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Describes the display of an advancement.
@@ -29,6 +29,7 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 + * The display is used in the chat, in the toast messages and the advancements
 + * screen.
 + */
++@NullMarked
 +public interface AdvancementDisplay {
 +
 +    /**
@@ -39,7 +40,6 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +     *
 +     * @return the frame type
 +     */
-+    @NotNull
 +    Frame frame();
 +
 +    /**
@@ -47,7 +47,6 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +     *
 +     * @return the title
 +     */
-+    @NotNull
 +    Component title();
 +
 +    /**
@@ -55,7 +54,6 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +     *
 +     * @return the description
 +     */
-+    @NotNull
 +    Component description();
 +
 +    /**
@@ -63,7 +61,6 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +     *
 +     * @return a copy of the icon
 +     */
-+    @NotNull
 +    ItemStack icon();
 +
 +    /**
@@ -104,8 +101,7 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +     *
 +     * @return the background texture path
 +     */
-+    @Nullable
-+    NamespacedKey backgroundPath();
++    @Nullable NamespacedKey backgroundPath();
 +
 +    /**
 +     * Gets the formatted display name for this display. This
@@ -115,7 +111,7 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +     * @return the display name
 +     * @see org.bukkit.advancement.Advancement#displayName()
 +     */
-+    @NotNull Component displayName();
++    Component displayName();
 +
 +    /**
 +     * Defines how the {@link #icon()} appears in the advancements screen and
@@ -148,7 +144,7 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +        private final String name;
 +        private final TextColor color;
 +
-+        Frame(String name, TextColor color) {
++        Frame(final String name, final TextColor color) {
 +            this.name = name;
 +            this.color = color;
 +        }
@@ -158,7 +154,6 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +         *
 +         * @return the text color
 +         */
-+        @NotNull
 +        public TextColor color() {
 +            return this.color;
 +        }
@@ -171,7 +166,6 @@ index 0000000000000000000000000000000000000000..19202e17f362fdffca472178b102d133
 +         * @return the toast message key
 +         */
 +        @Override
-+        @NotNull
 +        public String translationKey() {
 +            return "advancements.toast." + this.name;
 +        }
diff --git a/patches/api/0320-Bucketable-API.patch b/patches/api/0320-Bucketable-API.patch
index 26dbdc9f5d..b954c4c698 100644
--- a/patches/api/0320-Bucketable-API.patch
+++ b/patches/api/0320-Bucketable-API.patch
@@ -6,20 +6,21 @@ Subject: [PATCH] Bucketable API
 
 diff --git a/src/main/java/io/papermc/paper/entity/Bucketable.java b/src/main/java/io/papermc/paper/entity/Bucketable.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..84e360a16de956834a91142d45e4b5a0fe3d3a92
+index 0000000000000000000000000000000000000000..a63c3d0fe50f5808215ed169b81269112f76ec1b
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/entity/Bucketable.java
-@@ -0,0 +1,42 @@
+@@ -0,0 +1,41 @@
 +package io.papermc.paper.entity;
 +
 +import org.bukkit.Sound;
 +import org.bukkit.entity.Entity;
 +import org.bukkit.inventory.ItemStack;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents an entity that can be bucketed.
 + */
++@NullMarked
 +public interface Bucketable extends Entity {
 +
 +    /**
@@ -41,7 +42,6 @@ index 0000000000000000000000000000000000000000..84e360a16de956834a91142d45e4b5a0
 +     *
 +     * @return bucket form
 +     */
-+    @NotNull
 +    ItemStack getBaseBucketItem();
 +
 +    /**
@@ -49,7 +49,6 @@ index 0000000000000000000000000000000000000000..84e360a16de956834a91142d45e4b5a0
 +     * is picked up in a bucket.
 +     * @return bucket pickup sound
 +     */
-+    @NotNull
 +    Sound getPickupSound();
 +}
 diff --git a/src/main/java/org/bukkit/entity/Axolotl.java b/src/main/java/org/bukkit/entity/Axolotl.java
diff --git a/patches/api/0336-Custom-Potion-Mixes.patch b/patches/api/0336-Custom-Potion-Mixes.patch
index ae965ae441..7b6c776037 100644
--- a/patches/api/0336-Custom-Potion-Mixes.patch
+++ b/patches/api/0336-Custom-Potion-Mixes.patch
@@ -6,28 +6,26 @@ Subject: [PATCH] Custom Potion Mixes
 
 diff --git a/src/main/java/io/papermc/paper/potion/PotionMix.java b/src/main/java/io/papermc/paper/potion/PotionMix.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..3fc922ebf972418b84181cd02e68d8ef0efd739b
+index 0000000000000000000000000000000000000000..01b2a7c7a6bf328b3f7c30db3be0bfb8156ebc89
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/potion/PotionMix.java
-@@ -0,0 +1,105 @@
+@@ -0,0 +1,103 @@
 +package io.papermc.paper.potion;
 +
++import java.util.Objects;
 +import java.util.function.Predicate;
 +import org.bukkit.Keyed;
 +import org.bukkit.NamespacedKey;
 +import org.bukkit.inventory.ItemStack;
 +import org.bukkit.inventory.RecipeChoice;
-+import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
-+
-+import java.util.Objects;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents a potion mix made in a Brewing Stand.
 + */
-+@ApiStatus.NonExtendable
-+public class PotionMix implements Keyed {
++@NullMarked
++public final class PotionMix implements Keyed {
 +
 +    private final NamespacedKey key;
 +    private final ItemStack result;
@@ -42,7 +40,7 @@ index 0000000000000000000000000000000000000000..3fc922ebf972418b84181cd02e68d8ef
 +     * @param input the input placed into the bottom 3 slots
 +     * @param ingredient the ingredient placed into the top slot
 +     */
-+    public PotionMix(final @NotNull NamespacedKey key, final @NotNull ItemStack result, final @NotNull RecipeChoice input, final @NotNull RecipeChoice ingredient) {
++    public PotionMix(final NamespacedKey key, final ItemStack result, final RecipeChoice input, final RecipeChoice ingredient) {
 +        this.key = key;
 +        this.result = result;
 +        this.input = input;
@@ -57,12 +55,12 @@ index 0000000000000000000000000000000000000000..3fc922ebf972418b84181cd02e68d8ef
 +     * @return a new RecipeChoice
 +     */
 +    @Contract(value = "_ -> new", pure = true)
-+    public static @NotNull RecipeChoice createPredicateChoice(final @NotNull Predicate<? super ItemStack> stackPredicate) {
++    public static RecipeChoice createPredicateChoice(final Predicate<? super ItemStack> stackPredicate) {
 +        return new PredicateRecipeChoice(stackPredicate);
 +    }
 +
 +    @Override
-+    public @NotNull NamespacedKey getKey() {
++    public NamespacedKey getKey() {
 +        return this.key;
 +    }
 +
@@ -71,7 +69,7 @@ index 0000000000000000000000000000000000000000..3fc922ebf972418b84181cd02e68d8ef
 +     *
 +     * @return the result itemstack
 +     */
-+    public @NotNull ItemStack getResult() {
++    public ItemStack getResult() {
 +        return this.result;
 +    }
 +
@@ -80,7 +78,7 @@ index 0000000000000000000000000000000000000000..3fc922ebf972418b84181cd02e68d8ef
 +     *
 +     * @return the bottom 3 slot ingredients
 +     */
-+    public @NotNull RecipeChoice getInput() {
++    public RecipeChoice getInput() {
 +        return this.input;
 +    }
 +
@@ -89,7 +87,7 @@ index 0000000000000000000000000000000000000000..3fc922ebf972418b84181cd02e68d8ef
 +     *
 +     * @return the top slot input
 +     */
-+    public @NotNull RecipeChoice getIngredient() {
++    public RecipeChoice getIngredient() {
 +        return this.ingredient;
 +    }
 +
@@ -117,21 +115,20 @@ index 0000000000000000000000000000000000000000..3fc922ebf972418b84181cd02e68d8ef
 +}
 diff --git a/src/main/java/io/papermc/paper/potion/PredicateRecipeChoice.java b/src/main/java/io/papermc/paper/potion/PredicateRecipeChoice.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..3ede1e8f7bf0436fdc5bf395c0f9eaf11c252453
+index 0000000000000000000000000000000000000000..c252b432a9df5fd7da71a5eecba37a8844820700
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/potion/PredicateRecipeChoice.java
-@@ -0,0 +1,33 @@
+@@ -0,0 +1,32 @@
 +package io.papermc.paper.potion;
 +
 +import java.util.function.Predicate;
 +import org.bukkit.inventory.ItemStack;
 +import org.bukkit.inventory.RecipeChoice;
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.framework.qual.DefaultQualifier;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
-+@DefaultQualifier(NonNull.class)
++@NullMarked
 +record PredicateRecipeChoice(Predicate<? super ItemStack> itemStackPredicate) implements RecipeChoice, Cloneable {
 +
 +    @Override
@@ -155,7 +152,7 @@ index 0000000000000000000000000000000000000000..3ede1e8f7bf0436fdc5bf395c0f9eaf1
 +    }
 +}
 diff --git a/src/main/java/org/bukkit/Bukkit.java b/src/main/java/org/bukkit/Bukkit.java
-index aa1795b9640a5e39cc5063dd3c389f6d5815ed36..30cb0f2c4d53a7ad473812810c4f50173b7d7391 100644
+index e2d3e42b403dce454988c3ae3e44bcd89337b1cf..22021582b2f490ea2db87f2d3fe8a99b44d4f457 100644
 --- a/src/main/java/org/bukkit/Bukkit.java
 +++ b/src/main/java/org/bukkit/Bukkit.java
 @@ -2641,6 +2641,15 @@ public final class Bukkit {
@@ -175,7 +172,7 @@ index aa1795b9640a5e39cc5063dd3c389f6d5815ed36..30cb0f2c4d53a7ad473812810c4f5017
  
      @NotNull
 diff --git a/src/main/java/org/bukkit/Server.java b/src/main/java/org/bukkit/Server.java
-index 65060c06c1e5521656bd88547b8d0df5975c1d29..7c33c9489e0f3c4429e9bc30d87a3f4c29ca010f 100644
+index 5dd7ce5c008c852dbeb0474a70e9357230406318..178e91f3ad918c1a5600d6e9a14a21d478f7e1df 100644
 --- a/src/main/java/org/bukkit/Server.java
 +++ b/src/main/java/org/bukkit/Server.java
 @@ -2304,5 +2304,12 @@ public interface Server extends PluginMessageRecipient, net.kyori.adventure.audi
diff --git a/patches/api/0346-Add-EntityDyeEvent-and-CollarColorable-interface.patch b/patches/api/0346-Add-EntityDyeEvent-and-CollarColorable-interface.patch
index 33de736229..cef3e66464 100644
--- a/patches/api/0346-Add-EntityDyeEvent-and-CollarColorable-interface.patch
+++ b/patches/api/0346-Add-EntityDyeEvent-and-CollarColorable-interface.patch
@@ -6,19 +6,20 @@ Subject: [PATCH] Add EntityDyeEvent and CollarColorable interface
 
 diff --git a/src/main/java/io/papermc/paper/entity/CollarColorable.java b/src/main/java/io/papermc/paper/entity/CollarColorable.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..bb68e6a2528eee81eb3f26f22b9c35508f1e69c1
+index 0000000000000000000000000000000000000000..205b561c76386c02c827694b17ea50175a3c84ff
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/entity/CollarColorable.java
-@@ -0,0 +1,25 @@
+@@ -0,0 +1,26 @@
 +package io.papermc.paper.entity;
 +
 +import org.bukkit.DyeColor;
 +import org.bukkit.entity.LivingEntity;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Entities that can have their collars colored.
 + */
++@NullMarked
 +public interface CollarColorable extends LivingEntity {
 +
 +    /**
@@ -26,14 +27,14 @@ index 0000000000000000000000000000000000000000..bb68e6a2528eee81eb3f26f22b9c3550
 +     *
 +     * @return the color of the collar
 +     */
-+    @NotNull DyeColor getCollarColor();
++    DyeColor getCollarColor();
 +
 +    /**
 +     * Set the collar color of this entity
 +     *
 +     * @param color the color to apply
 +     */
-+    void setCollarColor(@NotNull DyeColor color);
++    void setCollarColor(DyeColor color);
 +}
 diff --git a/src/main/java/io/papermc/paper/event/entity/EntityDyeEvent.java b/src/main/java/io/papermc/paper/event/entity/EntityDyeEvent.java
 new file mode 100644
diff --git a/patches/api/0369-Add-Moving-Piston-API.patch b/patches/api/0369-Add-Moving-Piston-API.patch
index 8f889f1e3d..e93ac68dd2 100644
--- a/patches/api/0369-Add-Moving-Piston-API.patch
+++ b/patches/api/0369-Add-Moving-Piston-API.patch
@@ -6,17 +6,18 @@ Subject: [PATCH] Add Moving Piston API
 
 diff --git a/src/main/java/io/papermc/paper/block/MovingPiston.java b/src/main/java/io/papermc/paper/block/MovingPiston.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..ee7c85abf66dc11920bb29f9ce3b407121a665ee
+index 0000000000000000000000000000000000000000..962b92d487b3c442d2fe8b665ec3b2d375aaa9aa
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/block/MovingPiston.java
-@@ -0,0 +1,43 @@
+@@ -0,0 +1,42 @@
 +package io.papermc.paper.block;
 +
 +import org.bukkit.block.BlockFace;
 +import org.bukkit.block.TileState;
 +import org.bukkit.block.data.BlockData;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
++@NullMarked
 +public interface MovingPiston extends TileState {
 +
 +    /**
@@ -24,7 +25,6 @@ index 0000000000000000000000000000000000000000..ee7c85abf66dc11920bb29f9ce3b4071
 +     *
 +     * @return the pushed block
 +     */
-+    @NotNull
 +    BlockData getMovingBlock();
 +
 +    /**
@@ -33,7 +33,6 @@ index 0000000000000000000000000000000000000000..ee7c85abf66dc11920bb29f9ce3b4071
 +     *
 +     * @return the direction
 +     */
-+    @NotNull
 +    BlockFace getDirection();
 +
 +    /**
diff --git a/patches/api/0375-Add-Tick-TemporalUnit.patch b/patches/api/0375-Add-Tick-TemporalUnit.patch
index 562eb00082..2f5ad025dd 100644
--- a/patches/api/0375-Add-Tick-TemporalUnit.patch
+++ b/patches/api/0375-Add-Tick-TemporalUnit.patch
@@ -6,46 +6,50 @@ Subject: [PATCH] Add Tick TemporalUnit
 
 diff --git a/src/main/java/io/papermc/paper/util/Tick.java b/src/main/java/io/papermc/paper/util/Tick.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..10430f02e1d1e654383154c04473f07469bc7fee
+index 0000000000000000000000000000000000000000..1b264819c6faf2a4390d76350deb8e93804c6772
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/util/Tick.java
-@@ -0,0 +1,95 @@
+@@ -0,0 +1,101 @@
 +package io.papermc.paper.util;
 +
-+import net.kyori.adventure.util.Ticks;
-+import org.jetbrains.annotations.NotNull;
-+
 +import java.time.Duration;
 +import java.time.temporal.ChronoUnit;
 +import java.time.temporal.Temporal;
 +import java.time.temporal.TemporalUnit;
 +import java.util.Objects;
++import net.kyori.adventure.util.Ticks;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A TemporalUnit that represents the target length of one server tick. This is defined
 + * as 50 milliseconds. Note that this class is not for measuring the length that a tick
 + * took, rather it is used for simple conversion between times and ticks.
++ *
 + * @see #tick()
 + */
++@NullMarked
 +public final class Tick implements TemporalUnit {
++
 +    private static final Tick INSTANCE = new Tick(Ticks.SINGLE_TICK_DURATION_MS);
 +
 +    private final long milliseconds;
 +
 +    /**
 +     * Gets the instance of the tick temporal unit.
++     *
 +     * @return the tick instance
 +     */
-+    public static @NotNull Tick tick() {
++    public static Tick tick() {
 +        return INSTANCE;
 +    }
 +
 +    /**
 +     * Creates a new tick.
++     *
 +     * @param length the length of the tick in milliseconds
 +     * @see #tick()
 +     */
-+    private Tick(long length) {
++    private Tick(final long length) {
 +        this.milliseconds = length;
 +    }
 +
@@ -53,27 +57,29 @@ index 0000000000000000000000000000000000000000..10430f02e1d1e654383154c04473f074
 +     * Creates a duration from an amount of ticks. This is shorthand for
 +     * {@link Duration#of(long, TemporalUnit)} called with the amount of ticks and
 +     * {@link #tick()}.
++     *
 +     * @param ticks the amount of ticks
 +     * @return the duration
 +     */
-+    public static @NotNull Duration of(long ticks) {
++    public static Duration of(final long ticks) {
 +        return Duration.of(ticks, INSTANCE);
 +    }
 +
 +    /**
 +     * Gets the number of whole ticks that occur in the provided duration. Note that this
 +     * method returns an {@code int} as this is the unit that Minecraft stores ticks in.
++     *
 +     * @param duration the duration
 +     * @return the number of whole ticks in this duration
 +     * @throws ArithmeticException if the duration is zero or an overflow occurs
 +     */
-+    public int fromDuration(@NotNull Duration duration) {
++    public int fromDuration(final Duration duration) {
 +        Objects.requireNonNull(duration, "duration cannot be null");
 +        return Math.toIntExact(Math.floorDiv(duration.toMillis(), this.milliseconds));
 +    }
 +
 +    @Override
-+    public @NotNull Duration getDuration() {
++    public Duration getDuration() {
 +        return Duration.ofMillis(this.milliseconds);
 +    }
 +
@@ -96,12 +102,12 @@ index 0000000000000000000000000000000000000000..10430f02e1d1e654383154c04473f074
 +
 +    @SuppressWarnings("unchecked") // following ChronoUnit#addTo
 +    @Override
-+    public <R extends Temporal> @NotNull R addTo(@NotNull R temporal, long amount) {
-+        return (R) temporal.plus(getDuration().multipliedBy(amount));
++    public <R extends Temporal> R addTo(final R temporal, final long amount) {
++        return (R) temporal.plus(this.getDuration().multipliedBy(amount));
 +    }
 +
 +    @Override
-+    public long between(@NotNull Temporal start, @NotNull Temporal end) {
++    public long between(final Temporal start, final Temporal end) {
 +        return start.until(end, ChronoUnit.MILLIS) / this.milliseconds;
 +    }
 +}
diff --git a/patches/api/0376-Friction-API.patch b/patches/api/0376-Friction-API.patch
index 01f4286418..7e07d5afbb 100644
--- a/patches/api/0376-Friction-API.patch
+++ b/patches/api/0376-Friction-API.patch
@@ -6,7 +6,7 @@ Subject: [PATCH] Friction API
 
 diff --git a/src/main/java/io/papermc/paper/entity/Frictional.java b/src/main/java/io/papermc/paper/entity/Frictional.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..6eb88c664d873506372ad14075bfcbe42958126f
+index 0000000000000000000000000000000000000000..315558d8a592f7238f45fd1e68b70476e721be92
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/entity/Frictional.java
 @@ -0,0 +1,35 @@
@@ -14,11 +14,12 @@ index 0000000000000000000000000000000000000000..6eb88c664d873506372ad14075bfcbe4
 +
 +import net.kyori.adventure.util.TriState;
 +import org.bukkit.entity.Entity;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents an {@link Entity} that can experience friction with the air and ground.
 + */
++@NullMarked
 +public interface Frictional {
 +
 +    /**
@@ -29,7 +30,6 @@ index 0000000000000000000000000000000000000000..6eb88c664d873506372ad14075bfcbe4
 +     *
 +     * @return the entity's friction state
 +     */
-+    @NotNull
 +    TriState getFrictionState();
 +
 +    /**
@@ -42,7 +42,7 @@ index 0000000000000000000000000000000000000000..6eb88c664d873506372ad14075bfcbe4
 +     *
 +     * @param state the new friction state to set for the entity
 +     */
-+    void setFrictionState(@NotNull TriState state);
++    void setFrictionState(TriState state);
 +
 +}
 diff --git a/src/main/java/org/bukkit/entity/Item.java b/src/main/java/org/bukkit/entity/Item.java
diff --git a/patches/api/0390-Add-Shearable-API.patch b/patches/api/0390-Add-Shearable-API.patch
index e39ebc2481..8dd853b0fb 100644
--- a/patches/api/0390-Add-Shearable-API.patch
+++ b/patches/api/0390-Add-Shearable-API.patch
@@ -6,19 +6,20 @@ Subject: [PATCH] Add Shearable API
 
 diff --git a/src/main/java/io/papermc/paper/entity/Shearable.java b/src/main/java/io/papermc/paper/entity/Shearable.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..0d5793790ab6a47525ad33033517361205756338
+index 0000000000000000000000000000000000000000..3991f2aa530c588f52e1f596d3b03743e8a8ecc4
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/entity/Shearable.java
-@@ -0,0 +1,43 @@
+@@ -0,0 +1,44 @@
 +package io.papermc.paper.entity;
 +
 +import net.kyori.adventure.sound.Sound;
 +import org.bukkit.entity.Entity;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents an entity that can be sheared.
 + */
++@NullMarked
 +public interface Shearable extends Entity {
 +
 +    /**
@@ -44,7 +45,7 @@ index 0000000000000000000000000000000000000000..0d5793790ab6a47525ad330335173612
 +     *
 +     * @param source Sound source to play any sound effects on
 +     */
-+    void shear(@NotNull Sound.Source source);
++    void shear(Sound.Source source);
 +
 +    /**
 +     * Gets if the entity would be able to be sheared or not naturally using shears.
diff --git a/patches/api/0441-Add-Lifecycle-Event-system.patch b/patches/api/0441-Add-Lifecycle-Event-system.patch
index cd999b16ab..31bfe9a70f 100644
--- a/patches/api/0441-Add-Lifecycle-Event-system.patch
+++ b/patches/api/0441-Add-Lifecycle-Event-system.patch
@@ -8,22 +8,20 @@ meant for managing resources across reloads and from points in the
 PluginBootstrap.
 
 diff --git a/src/main/java/io/papermc/paper/plugin/bootstrap/BootstrapContext.java b/src/main/java/io/papermc/paper/plugin/bootstrap/BootstrapContext.java
-index 70d5f9802f90605a5120ff2a000a2e9395f0aecc..c319f3bbfabdd39ee571c59d7bfc144c58232abc 100644
+index 4c47414fc08e1183b1e59369bacc4d7f7042f262..577a9d5aeae55a3b8452b6d873b51b30384c1fea 100644
 --- a/src/main/java/io/papermc/paper/plugin/bootstrap/BootstrapContext.java
 +++ b/src/main/java/io/papermc/paper/plugin/bootstrap/BootstrapContext.java
-@@ -1,6 +1,9 @@
+@@ -1,5 +1,7 @@
  package io.papermc.paper.plugin.bootstrap;
  
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEventManager;
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEventOwner;
  import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
+ import org.jspecify.annotations.NullMarked;
  
- /**
-  * Represents the context provided to a {@link PluginBootstrap} during both the bootstrapping and plugin
-@@ -10,5 +13,13 @@ import org.jetbrains.annotations.ApiStatus;
-  */
+@@ -12,5 +14,13 @@ import org.jspecify.annotations.NullMarked;
  @ApiStatus.Experimental
+ @NullMarked
  @ApiStatus.NonExtendable
 -public interface BootstrapContext extends PluginProviderContext {
 +public interface BootstrapContext extends PluginProviderContext, LifecycleEventOwner {
@@ -34,7 +32,7 @@ index 70d5f9802f90605a5120ff2a000a2e9395f0aecc..c319f3bbfabdd39ee571c59d7bfc144c
 +     *
 +     * @return the lifecycle event manager
 +     */
-+    @NotNull LifecycleEventManager<BootstrapContext> getLifecycleManager();
++    LifecycleEventManager<BootstrapContext> getLifecycleManager();
  }
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/LifecycleEvent.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/LifecycleEvent.java
 new file mode 100644
@@ -61,17 +59,17 @@ index 0000000000000000000000000000000000000000..0b8eafd3e79494d4a750cd9182387fba
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/LifecycleEventManager.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/LifecycleEventManager.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..3626ce3da17f20ec44f0c15baa13f40e1dc2bc9c
+index 0000000000000000000000000000000000000000..e05cdb7ab166f92e270ea1b85e75f465878d05f2
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/LifecycleEventManager.java
-@@ -0,0 +1,52 @@
+@@ -0,0 +1,53 @@
 +package io.papermc.paper.plugin.lifecycle.event;
 +
 +import io.papermc.paper.plugin.lifecycle.event.handler.LifecycleEventHandler;
 +import io.papermc.paper.plugin.lifecycle.event.handler.configuration.LifecycleEventHandlerConfiguration;
 +import io.papermc.paper.plugin.lifecycle.event.types.LifecycleEventType;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Manages a plugin's lifecycle events. Can be obtained
@@ -80,6 +78,7 @@ index 0000000000000000000000000000000000000000..3626ce3da17f20ec44f0c15baa13f40e
 + * @param <O> the owning type, {@link org.bukkit.plugin.Plugin} or {@link io.papermc.paper.plugin.bootstrap.BootstrapContext}
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface LifecycleEventManager<O extends LifecycleEventOwner> {
 +
@@ -102,7 +101,7 @@ index 0000000000000000000000000000000000000000..3626ce3da17f20ec44f0c15baa13f40e
 +     * @param eventHandler the handler for that event
 +     * @param <E> the type of the event object
 +     */
-+    default <E extends LifecycleEvent> void registerEventHandler(final @NotNull LifecycleEventType<? super O, ? extends E, ?> eventType, final @NotNull LifecycleEventHandler<? super E> eventHandler) {
++    default <E extends LifecycleEvent> void registerEventHandler(final LifecycleEventType<? super O, ? extends E, ?> eventType, final LifecycleEventHandler<? super E> eventHandler) {
 +        this.registerEventHandler(eventType.newHandler(eventHandler));
 +    }
 +
@@ -115,19 +114,19 @@ index 0000000000000000000000000000000000000000..3626ce3da17f20ec44f0c15baa13f40e
 +     *
 +     * @param handlerConfiguration the handler configuration to register
 +     */
-+    void registerEventHandler(@NotNull LifecycleEventHandlerConfiguration<? super O> handlerConfiguration);
++    void registerEventHandler(LifecycleEventHandlerConfiguration<? super O> handlerConfiguration);
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/LifecycleEventOwner.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/LifecycleEventOwner.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..1160474f94476b580426cec29756c4699e163bf7
+index 0000000000000000000000000000000000000000..ce5891eb110464a1c0cd7416712110851d010a1b
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/LifecycleEventOwner.java
-@@ -0,0 +1,24 @@
+@@ -0,0 +1,25 @@
 +package io.papermc.paper.plugin.lifecycle.event;
 +
 +import io.papermc.paper.plugin.configuration.PluginMeta;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Implemented by types that are considered owners
@@ -137,6 +136,7 @@ index 0000000000000000000000000000000000000000..1160474f94476b580426cec29756c469
 + * event handlers.
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface LifecycleEventOwner {
 +
@@ -145,19 +145,19 @@ index 0000000000000000000000000000000000000000..1160474f94476b580426cec29756c469
 +     *
 +     * @return the plugin meta
 +     */
-+    @NotNull PluginMeta getPluginMeta();
++    PluginMeta getPluginMeta();
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/LifecycleEventHandler.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/LifecycleEventHandler.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..8239ba3c0147c0e8e8d28987d3f543a67641892a
+index 0000000000000000000000000000000000000000..3093ef23dd92f86240854065f7a7bb6c11ecf4fe
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/LifecycleEventHandler.java
-@@ -0,0 +1,18 @@
+@@ -0,0 +1,19 @@
 +package io.papermc.paper.plugin.lifecycle.event.handler;
 +
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEvent;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A handler for a specific event. Can be implemented
@@ -166,22 +166,24 @@ index 0000000000000000000000000000000000000000..8239ba3c0147c0e8e8d28987d3f543a6
 + * @param <E> the event
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@FunctionalInterface
 +public interface LifecycleEventHandler<E extends LifecycleEvent> {
 +
-+    void run(@NotNull E event);
++    void run(E event);
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/configuration/LifecycleEventHandlerConfiguration.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/configuration/LifecycleEventHandlerConfiguration.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..0831794fad1f6eb8960225909d40f4a3b20a2a3b
+index 0000000000000000000000000000000000000000..9b9f4655f222597b4e00519cfe128147bc438367
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/configuration/LifecycleEventHandlerConfiguration.java
-@@ -0,0 +1,18 @@
+@@ -0,0 +1,20 @@
 +package io.papermc.paper.plugin.lifecycle.event.handler.configuration;
 +
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEventOwner;
 +import io.papermc.paper.plugin.lifecycle.event.handler.LifecycleEventHandler;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Base type for constructing configured event handlers for
@@ -192,20 +194,22 @@ index 0000000000000000000000000000000000000000..0831794fad1f6eb8960225909d40f4a3
 + */
 +@SuppressWarnings("unused")
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface LifecycleEventHandlerConfiguration<O extends LifecycleEventOwner> {
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/configuration/MonitorLifecycleEventHandlerConfiguration.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/configuration/MonitorLifecycleEventHandlerConfiguration.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..d307ede51a66279f2eeef4e5b41c71779503f0d4
+index 0000000000000000000000000000000000000000..a2acc6e3867d6805c68e4c630aca3d14aa958a1d
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/configuration/MonitorLifecycleEventHandlerConfiguration.java
-@@ -0,0 +1,25 @@
+@@ -0,0 +1,27 @@
 +package io.papermc.paper.plugin.lifecycle.event.handler.configuration;
 +
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEventOwner;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Handler configuration for event types that allow "monitor" handlers.
@@ -213,6 +217,7 @@ index 0000000000000000000000000000000000000000..d307ede51a66279f2eeef4e5b41c7177
 + * @param <O> the required owner type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface MonitorLifecycleEventHandlerConfiguration<O extends LifecycleEventOwner> extends LifecycleEventHandlerConfiguration<O> {
 +
@@ -228,15 +233,16 @@ index 0000000000000000000000000000000000000000..d307ede51a66279f2eeef4e5b41c7177
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/configuration/PrioritizedLifecycleEventHandlerConfiguration.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/configuration/PrioritizedLifecycleEventHandlerConfiguration.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..1c404df0be359ceac7fb52fec03027c771395e07
+index 0000000000000000000000000000000000000000..100e5d169f1f644e54a042c697649f08fff1e6de
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/handler/configuration/PrioritizedLifecycleEventHandlerConfiguration.java
-@@ -0,0 +1,39 @@
+@@ -0,0 +1,41 @@
 +package io.papermc.paper.plugin.lifecycle.event.handler.configuration;
 +
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEventOwner;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Handler configuration that allows both "monitor" and prioritized handlers.
@@ -245,6 +251,7 @@ index 0000000000000000000000000000000000000000..1c404df0be359ceac7fb52fec03027c7
 + * @param <O> the required owner type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface PrioritizedLifecycleEventHandlerConfiguration<O extends LifecycleEventOwner> extends LifecycleEventHandlerConfiguration<O> {
 +
@@ -291,16 +298,16 @@ index 0000000000000000000000000000000000000000..fd9c3605a8f5e6bdd31e42f18a45154d
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/registrar/RegistrarEvent.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/registrar/RegistrarEvent.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..2e5758d1af6215f33f89b12984a5594df592147f
+index 0000000000000000000000000000000000000000..7dca6be092a8b5deca9c45b152a96ffe72fe2533
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/registrar/RegistrarEvent.java
-@@ -0,0 +1,27 @@
+@@ -0,0 +1,28 @@
 +package io.papermc.paper.plugin.lifecycle.event.registrar;
 +
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEvent;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A lifecycle event that exposes a {@link Registrar} of some kind
@@ -311,6 +318,7 @@ index 0000000000000000000000000000000000000000..2e5758d1af6215f33f89b12984a5594d
 + * @see ReloadableRegistrarEvent
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface RegistrarEvent<R extends Registrar> extends LifecycleEvent {
 +
@@ -320,19 +328,19 @@ index 0000000000000000000000000000000000000000..2e5758d1af6215f33f89b12984a5594d
 +     * @return the registrar
 +     */
 +    @Contract(pure = true)
-+    @NotNull R registrar();
++    R registrar();
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/registrar/ReloadableRegistrarEvent.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/registrar/ReloadableRegistrarEvent.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..b8b439bdad2e47c7c715fe30e0c1e69aa25374dd
+index 0000000000000000000000000000000000000000..9bce1c13c8092238939fbbec6b499d1ca85e5b89
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/registrar/ReloadableRegistrarEvent.java
-@@ -0,0 +1,38 @@
+@@ -0,0 +1,39 @@
 +package io.papermc.paper.plugin.lifecycle.event.registrar;
 +
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A lifecycle event that exposes a {@link Registrar} that is
@@ -342,6 +350,7 @@ index 0000000000000000000000000000000000000000..b8b439bdad2e47c7c715fe30e0c1e69a
 + * @see RegistrarEvent
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface ReloadableRegistrarEvent<R extends Registrar> extends RegistrarEvent<R> {
 +
@@ -351,7 +360,7 @@ index 0000000000000000000000000000000000000000..b8b439bdad2e47c7c715fe30e0c1e69a
 +     * @return the cause
 +     */
 +    @Contract(pure = true)
-+    @NotNull Cause cause();
++    Cause cause();
 +
 +    @ApiStatus.Experimental
 +    enum Cause {
@@ -368,10 +377,10 @@ index 0000000000000000000000000000000000000000..b8b439bdad2e47c7c715fe30e0c1e69a
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventType.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventType.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..92ea0374079a228ccc59c00fcf58abff2f6c46fe
+index 0000000000000000000000000000000000000000..75d9e20f53735ead4fa4aec478b4b72b85ca5e1e
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventType.java
-@@ -0,0 +1,73 @@
+@@ -0,0 +1,74 @@
 +package io.papermc.paper.plugin.lifecycle.event.types;
 +
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEvent;
@@ -383,7 +392,7 @@ index 0000000000000000000000000000000000000000..92ea0374079a228ccc59c00fcf58abff
 +import io.papermc.paper.plugin.lifecycle.event.handler.configuration.PrioritizedLifecycleEventHandlerConfiguration;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Base type for all types of lifecycle events. Differs from
@@ -397,6 +406,7 @@ index 0000000000000000000000000000000000000000..92ea0374079a228ccc59c00fcf58abff
 + * @param <C> the configuration type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface LifecycleEventType<O extends LifecycleEventOwner, E extends LifecycleEvent, C extends LifecycleEventHandlerConfiguration<O>> {
 +
@@ -406,7 +416,7 @@ index 0000000000000000000000000000000000000000..92ea0374079a228ccc59c00fcf58abff
 +     * @return the name
 +     */
 +    @Contract(pure = true)
-+    @NotNull String name();
++    String name();
 +
 +    /**
 +     * Create a configuration for this event with the specified
@@ -417,7 +427,7 @@ index 0000000000000000000000000000000000000000..92ea0374079a228ccc59c00fcf58abff
 +     * @see LifecycleEventManager#registerEventHandler(LifecycleEventHandlerConfiguration)
 +     */
 +    @Contract("_ -> new")
-+    @NotNull C newHandler(@NotNull LifecycleEventHandler<? super E> handler);
++    C newHandler(LifecycleEventHandler<? super E> handler);
 +
 +    /**
 +     * Lifecycle event type that supports separate registration
@@ -447,10 +457,10 @@ index 0000000000000000000000000000000000000000..92ea0374079a228ccc59c00fcf58abff
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventTypeProvider.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventTypeProvider.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..3b17f056d162dd42cae0d33cbbb22fece82fe525
+index 0000000000000000000000000000000000000000..e15e09c2a4d3f43db6a0159fa8af6179362ea8d6
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventTypeProvider.java
-@@ -0,0 +1,22 @@
+@@ -0,0 +1,24 @@
 +package io.papermc.paper.plugin.lifecycle.event.types;
 +
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEvent;
@@ -458,8 +468,10 @@ index 0000000000000000000000000000000000000000..3b17f056d162dd42cae0d33cbbb22fec
 +import java.util.Optional;
 +import java.util.ServiceLoader;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
++@NullMarked
 +interface LifecycleEventTypeProvider {
 +
 +    Optional<LifecycleEventTypeProvider> INSTANCE = ServiceLoader.load(LifecycleEventTypeProvider.class)
@@ -475,10 +487,10 @@ index 0000000000000000000000000000000000000000..3b17f056d162dd42cae0d33cbbb22fec
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..29476a1a82b3526ac03f21011d297d01462d153e
+index 0000000000000000000000000000000000000000..f70814de0d6c40b2c1c9921b8abdd1162e1d3995
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
-@@ -0,0 +1,52 @@
+@@ -0,0 +1,54 @@
 +package io.papermc.paper.plugin.lifecycle.event.types;
 +
 +import io.papermc.paper.plugin.bootstrap.BootstrapContext;
@@ -487,6 +499,7 @@ index 0000000000000000000000000000000000000000..29476a1a82b3526ac03f21011d297d01
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEventOwner;
 +import org.bukkit.plugin.Plugin;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Holds various types of lifecycle events for
@@ -494,6 +507,7 @@ index 0000000000000000000000000000000000000000..29476a1a82b3526ac03f21011d297d01
 + * in {@link LifecycleEventManager}.
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public final class LifecycleEvents {
 +
 +    //<editor-fold desc="helper methods" defaultstate="collapsed">
diff --git a/patches/api/0442-ItemStack-Tooltip-API.patch b/patches/api/0442-ItemStack-Tooltip-API.patch
index 3265b3b09a..4af91c3ade 100644
--- a/patches/api/0442-ItemStack-Tooltip-API.patch
+++ b/patches/api/0442-ItemStack-Tooltip-API.patch
@@ -6,20 +6,21 @@ Subject: [PATCH] ItemStack Tooltip API
 
 diff --git a/src/main/java/io/papermc/paper/inventory/tooltip/TooltipContext.java b/src/main/java/io/papermc/paper/inventory/tooltip/TooltipContext.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..39ac768b3c5148544cb1aaf2c817e661f6856f64
+index 0000000000000000000000000000000000000000..7e16f2645e956cbac8d0fc75ba8209f67fd1835c
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/inventory/tooltip/TooltipContext.java
-@@ -0,0 +1,75 @@
+@@ -0,0 +1,76 @@
 +package io.papermc.paper.inventory.tooltip;
 +
 +import org.bukkit.entity.Player;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Context for computing itemstack tooltips via
 + * {@link org.bukkit.inventory.ItemStack#computeTooltipLines(TooltipContext, Player)}
 + */
++@NullMarked
 +public interface TooltipContext {
 +
 +    /**
@@ -31,7 +32,7 @@ index 0000000000000000000000000000000000000000..39ac768b3c5148544cb1aaf2c817e661
 +     * @return a new context
 +     */
 +    @Contract("_, _ -> new")
-+    static @NotNull TooltipContext create(final boolean advanced, final boolean creative) {
++    static TooltipContext create(final boolean advanced, final boolean creative) {
 +        return new TooltipContextImpl(advanced, creative);
 +    }
 +
@@ -41,7 +42,7 @@ index 0000000000000000000000000000000000000000..39ac768b3c5148544cb1aaf2c817e661
 +     * @return a new context
 +     */
 +    @Contract("-> new")
-+    static @NotNull TooltipContext create() {
++    static TooltipContext create() {
 +        return new TooltipContextImpl(false, false);
 +    }
 +
@@ -74,7 +75,7 @@ index 0000000000000000000000000000000000000000..39ac768b3c5148544cb1aaf2c817e661
 +     * @return a new context
 +     */
 +    @Contract("-> new")
-+    @NotNull TooltipContext asAdvanced();
++    TooltipContext asAdvanced();
 +
 +    /**
 +     * Returns a new context with {@link #isCreative()}
@@ -83,27 +84,28 @@ index 0000000000000000000000000000000000000000..39ac768b3c5148544cb1aaf2c817e661
 +     * @return a new context
 +     */
 +    @Contract("-> new")
-+    @NotNull TooltipContext asCreative();
++    TooltipContext asCreative();
 +}
 diff --git a/src/main/java/io/papermc/paper/inventory/tooltip/TooltipContextImpl.java b/src/main/java/io/papermc/paper/inventory/tooltip/TooltipContextImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..c9c0ce750f93ae55e0b2d322a738919474d2d5dd
+index 0000000000000000000000000000000000000000..a649b90dfac6000c01579a48234a11383c731439
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/inventory/tooltip/TooltipContextImpl.java
-@@ -0,0 +1,16 @@
+@@ -0,0 +1,17 @@
 +package io.papermc.paper.inventory.tooltip;
 +
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
++@NullMarked
 +record TooltipContextImpl(boolean isAdvanced, boolean isCreative) implements TooltipContext {
 +
 +    @Override
-+    public @NotNull TooltipContext asCreative() {
++    public TooltipContext asCreative() {
 +        return new TooltipContextImpl(this.isAdvanced, true);
 +    }
 +
 +    @Override
-+    public @NotNull TooltipContext asAdvanced() {
++    public TooltipContext asAdvanced() {
 +        return new TooltipContextImpl(true, this.isCreative);
 +    }
 +}
@@ -119,7 +121,7 @@ index 141d5a964cc299284aecd4d34d57008a32f94247..31217b38e769f97801fa1afefeb223d1
 +    @NotNull java.util.List<net.kyori.adventure.text.Component> computeTooltipLines(@NotNull ItemStack itemStack, @NotNull io.papermc.paper.inventory.tooltip.TooltipContext tooltipContext, @Nullable org.bukkit.entity.Player player); // Paper - expose itemstack tooltip lines
  }
 diff --git a/src/main/java/org/bukkit/inventory/ItemStack.java b/src/main/java/org/bukkit/inventory/ItemStack.java
-index 43b8823d4af93febbd60d1b16b406a665373bacd..268baface3b58fba4f7c8a4d3f1b370fa1d26cee 100644
+index e6c69a54e0c1dc511fe5769f869dcecb13e04ed3..49390979cc0c68b8e719f2a2ce9e7d193c747959 100644
 --- a/src/main/java/org/bukkit/inventory/ItemStack.java
 +++ b/src/main/java/org/bukkit/inventory/ItemStack.java
 @@ -1124,4 +1124,21 @@ public class ItemStack implements Cloneable, ConfigurationSerializable, Translat
diff --git a/patches/api/0444-Add-FluidState-API.patch b/patches/api/0444-Add-FluidState-API.patch
index 3235c393f5..8f786918cb 100644
--- a/patches/api/0444-Add-FluidState-API.patch
+++ b/patches/api/0444-Add-FluidState-API.patch
@@ -6,22 +6,23 @@ Subject: [PATCH] Add FluidState API
 
 diff --git a/src/main/java/io/papermc/paper/block/fluid/FluidData.java b/src/main/java/io/papermc/paper/block/fluid/FluidData.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..913acd58547d97cafc1466f6e2b3b4d22cf0b02d
+index 0000000000000000000000000000000000000000..0750219fc68261e5c396636967e0b633ae17b72e
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/block/fluid/FluidData.java
-@@ -0,0 +1,68 @@
+@@ -0,0 +1,69 @@
 +package io.papermc.paper.block.fluid;
 +
 +import org.bukkit.Fluid;
 +import org.bukkit.Location;
 +import org.bukkit.util.Vector;
-+import org.jetbrains.annotations.NotNull;
 +import org.jetbrains.annotations.Range;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A representation of a fluid in a specific state of data.
 + * This type is not linked to a specific location and hence mostly resembles a {@link org.bukkit.block.data.BlockData}.
 + */
++@NullMarked
 +public interface FluidData extends Cloneable {
 +
 +    /**
@@ -29,14 +30,14 @@ index 0000000000000000000000000000000000000000..913acd58547d97cafc1466f6e2b3b4d2
 +     *
 +     * @return the fluid type
 +     */
-+    @NotNull Fluid getFluidType();
++    Fluid getFluidType();
 +
 +    /**
 +     * Returns a copy of this FluidData.
 +     *
 +     * @return a copy of the fluid data
 +     */
-+    @NotNull FluidData clone();
++    FluidData clone();
 +
 +    /**
 +     * Computes the direction of the flow of the liquid at the given location as a vector.
@@ -48,7 +49,7 @@ index 0000000000000000000000000000000000000000..913acd58547d97cafc1466f6e2b3b4d2
 +     * @param location - the location to check the liquid flow
 +     * @return the flow direction vector at the given location
 +     */
-+    @NotNull Vector computeFlowDirection(@NotNull Location location);
++    Vector computeFlowDirection(Location location);
 +
 +    /**
 +     * Returns the level of liquid this fluid data holds.
@@ -69,7 +70,7 @@ index 0000000000000000000000000000000000000000..913acd58547d97cafc1466f6e2b3b4d2
 +     * @return the height as a float value
 +     */
 +    @Range(from = 0, to = 1)
-+    float computeHeight(@NotNull Location location);
++    float computeHeight(Location location);
 +
 +    /**
 +     * Returns whether this fluid is a source block
diff --git a/patches/api/0445-add-number-format-api.patch b/patches/api/0445-add-number-format-api.patch
index 6d32302ad0..8d36669b0a 100644
--- a/patches/api/0445-add-number-format-api.patch
+++ b/patches/api/0445-add-number-format-api.patch
@@ -18,19 +18,20 @@ index 0000000000000000000000000000000000000000..486da6ebe0137bb3280e8b33c8e35e30
 +}
 diff --git a/src/main/java/io/papermc/paper/scoreboard/numbers/FixedFormat.java b/src/main/java/io/papermc/paper/scoreboard/numbers/FixedFormat.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..66e0569789d523076cb571fb32be78ecff74305b
+index 0000000000000000000000000000000000000000..3ef4595b692a13566c5c738050b83b0462094e9b
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/scoreboard/numbers/FixedFormat.java
-@@ -0,0 +1,19 @@
+@@ -0,0 +1,20 @@
 +package io.papermc.paper.scoreboard.numbers;
 +
 +import net.kyori.adventure.text.Component;
 +import net.kyori.adventure.text.ComponentLike;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A scoreboard number format that replaces the score number with a chat component.
 + */
++@NullMarked
 +public interface FixedFormat extends NumberFormat, ComponentLike {
 +
 +    /**
@@ -38,43 +39,45 @@ index 0000000000000000000000000000000000000000..66e0569789d523076cb571fb32be78ec
 +     *
 +     * @return the chat component
 +     */
-+    @NotNull Component component();
++    Component component();
 +
 +}
 diff --git a/src/main/java/io/papermc/paper/scoreboard/numbers/FixedFormatImpl.java b/src/main/java/io/papermc/paper/scoreboard/numbers/FixedFormatImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..969bbfcdb68ffb5a207207e20e4d79621900c0f5
+index 0000000000000000000000000000000000000000..be47bf438805f9ab84b241e564281ea9c287aa6e
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/scoreboard/numbers/FixedFormatImpl.java
-@@ -0,0 +1,12 @@
+@@ -0,0 +1,13 @@
 +package io.papermc.paper.scoreboard.numbers;
 +
 +import net.kyori.adventure.text.Component;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
-+record FixedFormatImpl(@NotNull Component component) implements FixedFormat {
++@NullMarked
++record FixedFormatImpl(Component component) implements FixedFormat {
 +
 +    @Override
-+    public @NotNull Component asComponent() {
++    public Component asComponent() {
 +        return this.component();
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/scoreboard/numbers/NumberFormat.java b/src/main/java/io/papermc/paper/scoreboard/numbers/NumberFormat.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..eadf637f5fc582a2af5db71274ac1f01b2a28913
+index 0000000000000000000000000000000000000000..7c093e4e9a2a67021da9025631a3c6fa7ac3ef35
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/scoreboard/numbers/NumberFormat.java
-@@ -0,0 +1,60 @@
+@@ -0,0 +1,61 @@
 +package io.papermc.paper.scoreboard.numbers;
 +
 +import net.kyori.adventure.text.ComponentLike;
 +import net.kyori.adventure.text.format.Style;
 +import net.kyori.adventure.text.format.StyleBuilderApplicable;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Describes a scoreboard number format that applies custom formatting to scoreboard scores.
 + */
++@NullMarked
 +public interface NumberFormat {
 +
 +    /**
@@ -82,7 +85,7 @@ index 0000000000000000000000000000000000000000..eadf637f5fc582a2af5db71274ac1f01
 +     *
 +     * @return a blank number format
 +     */
-+    static @NotNull NumberFormat blank() {
++    static NumberFormat blank() {
 +        return BlankFormatImpl.INSTANCE;
 +    }
 +
@@ -91,7 +94,7 @@ index 0000000000000000000000000000000000000000..eadf637f5fc582a2af5db71274ac1f01
 +     *
 +     * @return an un-styled number format
 +     */
-+    static @NotNull StyledFormat noStyle() {
++    static StyledFormat noStyle() {
 +        return StyledFormatImpl.NO_STYLE;
 +    }
 +
@@ -101,7 +104,7 @@ index 0000000000000000000000000000000000000000..eadf637f5fc582a2af5db71274ac1f01
 +     * @param style the style to apply on the number
 +     * @return a styled number format
 +     */
-+    static @NotNull StyledFormat styled(final @NotNull Style style) {
++    static StyledFormat styled(final Style style) {
 +        return new StyledFormatImpl(style);
 +    }
 +
@@ -111,7 +114,7 @@ index 0000000000000000000000000000000000000000..eadf637f5fc582a2af5db71274ac1f01
 +     * @param styleBuilderApplicables the style to apply on the number
 +     * @return a styled number format
 +     */
-+    static @NotNull StyledFormat styled(final @NotNull StyleBuilderApplicable @NotNull... styleBuilderApplicables) {
++    static StyledFormat styled(final StyleBuilderApplicable... styleBuilderApplicables) {
 +        return styled(Style.style(styleBuilderApplicables));
 +    }
 +
@@ -121,25 +124,26 @@ index 0000000000000000000000000000000000000000..eadf637f5fc582a2af5db71274ac1f01
 +     * @param component the component to replace the number with
 +     * @return a fixed number format
 +     */
-+    static @NotNull FixedFormat fixed(final @NotNull ComponentLike component) {
++    static FixedFormat fixed(final ComponentLike component) {
 +        return new FixedFormatImpl(component.asComponent());
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/scoreboard/numbers/StyledFormat.java b/src/main/java/io/papermc/paper/scoreboard/numbers/StyledFormat.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..fe844677d689c3afe5ff2b706d562724e4121137
+index 0000000000000000000000000000000000000000..cfb14bb1b338727a5d9eeaa7a73c40540b04dbed
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/scoreboard/numbers/StyledFormat.java
-@@ -0,0 +1,19 @@
+@@ -0,0 +1,20 @@
 +package io.papermc.paper.scoreboard.numbers;
 +
 +import net.kyori.adventure.text.format.Style;
 +import net.kyori.adventure.text.format.StyleBuilderApplicable;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A scoreboard number format that applies a custom formatting to the score number.
 + */
++@NullMarked
 +public interface StyledFormat extends NumberFormat, StyleBuilderApplicable {
 +
 +    /**
@@ -147,25 +151,26 @@ index 0000000000000000000000000000000000000000..fe844677d689c3afe5ff2b706d562724
 +     *
 +     * @return the style to apply
 +     */
-+    @NotNull Style style();
++    Style style();
 +
 +}
 diff --git a/src/main/java/io/papermc/paper/scoreboard/numbers/StyledFormatImpl.java b/src/main/java/io/papermc/paper/scoreboard/numbers/StyledFormatImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..0421e6c7cb32a912cf4aa281623c4311d5d1a34f
+index 0000000000000000000000000000000000000000..e288beb1596f2d4e7e602364955da4e8bc0de21c
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/scoreboard/numbers/StyledFormatImpl.java
-@@ -0,0 +1,13 @@
+@@ -0,0 +1,14 @@
 +package io.papermc.paper.scoreboard.numbers;
 +
 +import net.kyori.adventure.text.format.Style;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
-+record StyledFormatImpl(@NotNull Style style) implements StyledFormat {
++@NullMarked
++record StyledFormatImpl(Style style) implements StyledFormat {
 +    static final StyledFormat NO_STYLE = new StyledFormatImpl(Style.empty());
 +
 +    @Override
-+    public void styleApply(final Style.@NotNull Builder style) {
++    public void styleApply(final Style.Builder style) {
 +        style.merge(this.style);
 +    }
 +}
diff --git a/patches/api/0446-improve-BanList-types.patch b/patches/api/0446-improve-BanList-types.patch
index 47e1822e8b..bfb2a6a550 100644
--- a/patches/api/0446-improve-BanList-types.patch
+++ b/patches/api/0446-improve-BanList-types.patch
@@ -6,21 +6,22 @@ Subject: [PATCH] improve BanList types
 
 diff --git a/src/main/java/io/papermc/paper/ban/BanListType.java b/src/main/java/io/papermc/paper/ban/BanListType.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..2980abf2f41cb14f0ee5c829c365f8e304130618
+index 0000000000000000000000000000000000000000..fdd5cfdc8c2c2ba97a3ac3db57be5a0e13dc327d
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/ban/BanListType.java
-@@ -0,0 +1,29 @@
+@@ -0,0 +1,30 @@
 +package io.papermc.paper.ban;
 +
 +import org.bukkit.BanList;
 +import org.bukkit.ban.IpBanList;
 +import org.bukkit.ban.ProfileBanList;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents a ban-type that a {@link BanList} may track.
 + * It enforces the correct return value at compile time.
 + */
++@NullMarked
 +public interface BanListType<T> {
 +
 +    /**
@@ -37,21 +38,22 @@ index 0000000000000000000000000000000000000000..2980abf2f41cb14f0ee5c829c365f8e3
 +     *
 +     * @return the type class
 +     */
-+    @NotNull Class<T> typeClass();
++    Class<T> typeClass();
 +}
 diff --git a/src/main/java/io/papermc/paper/ban/BanListTypeImpl.java b/src/main/java/io/papermc/paper/ban/BanListTypeImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..1159e7cd29fbf11f3fa1448fcf9d0768e1bcb0a3
+index 0000000000000000000000000000000000000000..26d4df3cbf8d31790218095bb7fb1a1762e2b322
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/ban/BanListTypeImpl.java
-@@ -0,0 +1,8 @@
+@@ -0,0 +1,9 @@
 +package io.papermc.paper.ban;
 +
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
-+record BanListTypeImpl<T>(@NotNull Class<T> typeClass) implements BanListType<T> {
++@NullMarked
++record BanListTypeImpl<T>(Class<T> typeClass) implements BanListType<T> {
 +}
 diff --git a/src/main/java/org/bukkit/BanList.java b/src/main/java/org/bukkit/BanList.java
 index a77c0411a68a9bad33ddfb335b7a996a843e478c..739d9d3ec789e58c10c8d818a9ca59ce447600d5 100644
diff --git a/patches/api/0447-Suspicious-Effect-Entry-API.patch b/patches/api/0447-Suspicious-Effect-Entry-API.patch
index bcf3db2033..d591d57ce9 100644
--- a/patches/api/0447-Suspicious-Effect-Entry-API.patch
+++ b/patches/api/0447-Suspicious-Effect-Entry-API.patch
@@ -15,20 +15,21 @@ Co-authored-by: Yannick Lamprecht <yannicklamprecht@live.de>
 
 diff --git a/src/main/java/io/papermc/paper/potion/SuspiciousEffectEntry.java b/src/main/java/io/papermc/paper/potion/SuspiciousEffectEntry.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..6a96e339ff1466df5743b5d42a31ce6a67e48f16
+index 0000000000000000000000000000000000000000..6311ede3e3812da2ccdbcb19522facd7b2e3bd5c
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/potion/SuspiciousEffectEntry.java
-@@ -0,0 +1,38 @@
+@@ -0,0 +1,39 @@
 +package io.papermc.paper.potion;
 +
 +import org.bukkit.potion.PotionEffect;
 +import org.bukkit.potion.PotionEffectType;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents a {@link PotionEffectType} paired with a duration.
 + */
++@NullMarked
 +public sealed interface SuspiciousEffectEntry permits SuspiciousEffectEntryImpl {
 +
 +    /**
@@ -36,7 +37,7 @@ index 0000000000000000000000000000000000000000..6a96e339ff1466df5743b5d42a31ce6a
 +     *
 +     * @return effect type
 +     */
-+    @NotNull PotionEffectType effect();
++    PotionEffectType effect();
 +
 +    /**
 +     * Gets the duration for this effect instance.
@@ -53,22 +54,25 @@ index 0000000000000000000000000000000000000000..6a96e339ff1466df5743b5d42a31ce6a
 +     * @return new instance of an entry
 +     */
 +    @Contract(value = "_, _ -> new", pure = true)
-+    static @NotNull SuspiciousEffectEntry create(final @NotNull PotionEffectType effectType, final int duration) {
++    static SuspiciousEffectEntry create(final PotionEffectType effectType, final int duration) {
 +        return new SuspiciousEffectEntryImpl(effectType, duration);
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/potion/SuspiciousEffectEntryImpl.java b/src/main/java/io/papermc/paper/potion/SuspiciousEffectEntryImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..e5002ccaef9ea7a9db94296ad0d66cdae050cdd1
+index 0000000000000000000000000000000000000000..a91d37ee450944ea779bd6b61d416467948bb55f
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/potion/SuspiciousEffectEntryImpl.java
-@@ -0,0 +1,7 @@
+@@ -0,0 +1,10 @@
 +package io.papermc.paper.potion;
 +
 +import org.bukkit.potion.PotionEffectType;
-+import org.jetbrains.annotations.NotNull;
++import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
-+record SuspiciousEffectEntryImpl(@NotNull PotionEffectType effect, int duration) implements SuspiciousEffectEntry {
++@ApiStatus.Internal
++@NullMarked
++record SuspiciousEffectEntryImpl(PotionEffectType effect, int duration) implements SuspiciousEffectEntry {
 +}
 diff --git a/src/main/java/org/bukkit/entity/MushroomCow.java b/src/main/java/org/bukkit/entity/MushroomCow.java
 index 86c0043ef4e1288b6fe2f68a9b6d01c3de2c3454..3677f19ef1c05b76d946b1b2b491a6c3cec76140 100644
diff --git a/patches/api/0466-Brigadier-based-command-API.patch b/patches/api/0466-Brigadier-based-command-API.patch
index 34193bec69..701eb760a5 100644
--- a/patches/api/0466-Brigadier-based-command-API.patch
+++ b/patches/api/0466-Brigadier-based-command-API.patch
@@ -502,24 +502,25 @@ index 0000000000000000000000000000000000000000..9df87708206e26167a2c4934deff7fc6
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/BasicCommand.java b/src/main/java/io/papermc/paper/command/brigadier/BasicCommand.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..99a9a5ecc5010bcd30351f8844cb5d824c252523
+index 0000000000000000000000000000000000000000..c89d6c4c38e2390cb11ffba182f8741d3726cfd1
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/BasicCommand.java
-@@ -0,0 +1,60 @@
+@@ -0,0 +1,62 @@
 +package io.papermc.paper.command.brigadier;
 +
 +import java.util.Collection;
 +import java.util.Collections;
 +import org.bukkit.command.CommandSender;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Implementing this interface allows for easily creating "Bukkit-style" {@code String[] args} commands.
 + * The implementation handles converting the command to a representation compatible with Brigadier on registration, usually in the form of {@literal /commandlabel <greedy_string>}.
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@FunctionalInterface
 +public interface BasicCommand {
 +
@@ -530,7 +531,7 @@ index 0000000000000000000000000000000000000000..99a9a5ecc5010bcd30351f8844cb5d82
 +     * @param args the arguments of the command ignoring repeated spaces
 +     */
 +    @ApiStatus.OverrideOnly
-+    void execute(@NotNull CommandSourceStack commandSourceStack, @NotNull String[] args);
++    void execute(CommandSourceStack commandSourceStack, String[] args);
 +
 +    /**
 +     * Suggests possible completions for the given command {@link CommandSourceStack} and arguments.
@@ -540,7 +541,7 @@ index 0000000000000000000000000000000000000000..99a9a5ecc5010bcd30351f8844cb5d82
 +     * @return a collection of suggestions
 +     */
 +    @ApiStatus.OverrideOnly
-+    default @NotNull Collection<String> suggest(final @NotNull CommandSourceStack commandSourceStack, final @NotNull String[] args) {
++    default Collection<String> suggest(final CommandSourceStack commandSourceStack, final String[] args) {
 +        return Collections.emptyList();
 +    }
 +
@@ -552,8 +553,9 @@ index 0000000000000000000000000000000000000000..99a9a5ecc5010bcd30351f8844cb5d82
 +     * @see #permission()
 +     */
 +    @ApiStatus.OverrideOnly
-+    default boolean canUse(final @NotNull CommandSender sender) {
-+        return this.permission() == null || sender.hasPermission(this.permission());
++    default boolean canUse(final CommandSender sender) {
++        final String permission = this.permission();
++        return permission == null || sender.hasPermission(permission);
 +    }
 +
 +    /**
@@ -588,18 +590,18 @@ index 0000000000000000000000000000000000000000..7e24babf746de474c8deec4b147e2203
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/CommandSourceStack.java b/src/main/java/io/papermc/paper/command/brigadier/CommandSourceStack.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..54288dbe7185b875a74184f002ee4de4405e91b1
+index 0000000000000000000000000000000000000000..ac6f5b754a15e85ce09de4ed4cdee2044b45022c
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/CommandSourceStack.java
-@@ -0,0 +1,50 @@
+@@ -0,0 +1,51 @@
 +package io.papermc.paper.command.brigadier;
 +
 +import org.bukkit.Location;
 +import org.bukkit.command.CommandSender;
 +import org.bukkit.entity.Entity;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * The command source type for Brigadier commands registered using Paper API.
@@ -613,8 +615,9 @@ index 0000000000000000000000000000000000000000..54288dbe7185b875a74184f002ee4de4
 + * exist yet, or no specific sender is available. Methods on such a {@link CommandSender}
 + * will either have no effect or throw an {@link UnsupportedOperationException}.</p>
 + */
-+@ApiStatus.NonExtendable
 +@ApiStatus.Experimental
++@NullMarked
++@ApiStatus.NonExtendable
 +public interface CommandSourceStack {
 +
 +    /**
@@ -622,7 +625,7 @@ index 0000000000000000000000000000000000000000..54288dbe7185b875a74184f002ee4de4
 +     *
 +     * @return a cloned location instance.
 +     */
-+    @NotNull Location getLocation();
++    Location getLocation();
 +
 +    /**
 +     * Gets the command sender that executed this command.
@@ -631,7 +634,7 @@ index 0000000000000000000000000000000000000000..54288dbe7185b875a74184f002ee4de4
 +     *
 +     * @return the command sender instance
 +     */
-+    @NotNull CommandSender getSender();
++    CommandSender getSender();
 +
 +    /**
 +     * Gets the entity that executes this command.
@@ -644,10 +647,10 @@ index 0000000000000000000000000000000000000000..54288dbe7185b875a74184f002ee4de4
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/Commands.java b/src/main/java/io/papermc/paper/command/brigadier/Commands.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe02600465c
+index 0000000000000000000000000000000000000000..e32559772a39af781d89de101b3f7483a339e317
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/Commands.java
-@@ -0,0 +1,266 @@
+@@ -0,0 +1,267 @@
 +package io.papermc.paper.command.brigadier;
 +
 +import com.mojang.brigadier.CommandDispatcher;
@@ -664,9 +667,9 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +import java.util.Collections;
 +import java.util.Set;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * The registrar for custom commands. Supports Brigadier commands and {@link BasicCommand}.
@@ -709,6 +712,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 + * @see io.papermc.paper.plugin.lifecycle.event.types.LifecycleEvents#COMMANDS
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface Commands extends Registrar {
 +
@@ -718,7 +722,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param literal literal name
 +     * @return a new builder instance
 +     */
-+    static @NotNull LiteralArgumentBuilder<CommandSourceStack> literal(final @NotNull String literal) {
++    static LiteralArgumentBuilder<CommandSourceStack> literal(final String literal) {
 +        return LiteralArgumentBuilder.literal(literal);
 +    }
 +
@@ -730,7 +734,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param <T>          the generic type of the argument value
 +     * @return a new required argument builder
 +     */
-+    static <T> @NotNull RequiredArgumentBuilder<CommandSourceStack, T> argument(final @NotNull String name, final @NotNull ArgumentType<T> argumentType) {
++    static <T> RequiredArgumentBuilder<CommandSourceStack, T> argument(final String name, final ArgumentType<T> argumentType) {
 +        return RequiredArgumentBuilder.argument(name, argumentType);
 +    }
 +
@@ -754,7 +758,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @return the dispatcher instance
 +     */
 +    @ApiStatus.Experimental
-+    @NotNull CommandDispatcher<CommandSourceStack> getDispatcher();
++    CommandDispatcher<CommandSourceStack> getDispatcher();
 +
 +    /**
 +     * Registers a command for the current plugin context.
@@ -768,7 +772,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param node the built literal command node
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    default @Unmodifiable @NotNull Set<String> register(final @NotNull LiteralCommandNode<CommandSourceStack> node) {
++    default @Unmodifiable Set<String> register(final LiteralCommandNode<CommandSourceStack> node) {
 +        return this.register(node, null, Collections.emptyList());
 +    }
 +
@@ -785,7 +789,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param description the help description for the root literal node
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    default @Unmodifiable @NotNull Set<String> register(final @NotNull LiteralCommandNode<CommandSourceStack> node, final @Nullable String description) {
++    default @Unmodifiable Set<String> register(final LiteralCommandNode<CommandSourceStack> node, final @Nullable String description) {
 +        return this.register(node, description, Collections.emptyList());
 +    }
 +
@@ -802,7 +806,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param aliases a collection of aliases to register the literal node's command to
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    default @Unmodifiable @NotNull Set<String> register(final @NotNull LiteralCommandNode<CommandSourceStack> node, final @NotNull Collection<String> aliases) {
++    default @Unmodifiable Set<String> register(final LiteralCommandNode<CommandSourceStack> node, final Collection<String> aliases) {
 +        return this.register(node, null, aliases);
 +    }
 +
@@ -820,7 +824,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param aliases     a collection of aliases to register the literal node's command to
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    @Unmodifiable @NotNull Set<String> register(@NotNull LiteralCommandNode<CommandSourceStack> node, @Nullable String description, @NotNull Collection<String> aliases);
++    @Unmodifiable Set<String> register(LiteralCommandNode<CommandSourceStack> node, @Nullable String description, Collection<String> aliases);
 +
 +    /**
 +     * Registers a command for a plugin.
@@ -837,7 +841,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param aliases     a collection of aliases to register the literal node's command to
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    @Unmodifiable @NotNull Set<String> register(@NotNull PluginMeta pluginMeta, @NotNull LiteralCommandNode<CommandSourceStack> node, @Nullable String description, @NotNull Collection<String> aliases);
++    @Unmodifiable Set<String> register(PluginMeta pluginMeta, LiteralCommandNode<CommandSourceStack> node, @Nullable String description, Collection<String> aliases);
 +
 +    /**
 +     * This allows configuring the registration of your command, which is not intended for public use.
@@ -854,7 +858,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * See {@link CommandRegistrationFlag} for a more indepth explanation of this method's use-case.
 +     */
 +    @ApiStatus.Internal
-+    @Unmodifiable @NotNull Set<String> registerWithFlags(@NotNull PluginMeta pluginMeta, @NotNull LiteralCommandNode<CommandSourceStack> node, @Nullable String description, @NotNull Collection<String> aliases, @NotNull Set<CommandRegistrationFlag> flags);
++    @Unmodifiable Set<String> registerWithFlags(PluginMeta pluginMeta, LiteralCommandNode<CommandSourceStack> node, @Nullable String description, Collection<String> aliases, Set<CommandRegistrationFlag> flags);
 +
 +    /**
 +     * Registers a command under the same logic as {@link Commands#register(LiteralCommandNode, String, Collection)}.
@@ -863,7 +867,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param basicCommand the basic command instance to register
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    default @Unmodifiable @NotNull Set<String> register(final @NotNull String label, final @NotNull BasicCommand basicCommand) {
++    default @Unmodifiable Set<String> register(final String label, final BasicCommand basicCommand) {
 +        return this.register(label, null, Collections.emptyList(), basicCommand);
 +    }
 +
@@ -875,7 +879,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param basicCommand the basic command instance to register
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    default @Unmodifiable @NotNull Set<String> register(final @NotNull String label, final @Nullable String description, final @NotNull BasicCommand basicCommand) {
++    default @Unmodifiable Set<String> register(final String label, final @Nullable String description, final BasicCommand basicCommand) {
 +        return this.register(label, description, Collections.emptyList(), basicCommand);
 +    }
 +
@@ -887,7 +891,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param basicCommand the basic command instance to register
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    default @Unmodifiable @NotNull Set<String> register(final @NotNull String label, final @NotNull Collection<String> aliases, final @NotNull BasicCommand basicCommand) {
++    default @Unmodifiable Set<String> register(final String label, final Collection<String> aliases, final BasicCommand basicCommand) {
 +        return this.register(label, null, aliases, basicCommand);
 +    }
 +
@@ -900,7 +904,7 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param basicCommand the basic command instance to register
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    @Unmodifiable @NotNull Set<String> register(@NotNull String label, @Nullable String description, @NotNull Collection<String> aliases, @NotNull BasicCommand basicCommand);
++    @Unmodifiable Set<String> register(String label, @Nullable String description, Collection<String> aliases, BasicCommand basicCommand);
 +
 +    /**
 +     * Registers a command under the same logic as {@link Commands#register(PluginMeta, LiteralCommandNode, String, Collection)}.
@@ -912,26 +916,27 @@ index 0000000000000000000000000000000000000000..ce60b618de10da7638f5aefa974aebe0
 +     * @param basicCommand the basic command instance to register
 +     * @return successfully registered root command labels (including aliases and namespaced variants)
 +     */
-+    @Unmodifiable @NotNull Set<String> register(@NotNull PluginMeta pluginMeta, @NotNull String label, @Nullable String description, @NotNull Collection<String> aliases, @NotNull BasicCommand basicCommand);
++    @Unmodifiable Set<String> register(PluginMeta pluginMeta, String label, @Nullable String description, Collection<String> aliases, BasicCommand basicCommand);
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/MessageComponentSerializer.java b/src/main/java/io/papermc/paper/command/brigadier/MessageComponentSerializer.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..57061a3dd738416c2045e641b6080dc3f096de1a
+index 0000000000000000000000000000000000000000..19f3dc12426be09613a13b5889f77627a81305f4
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/MessageComponentSerializer.java
-@@ -0,0 +1,24 @@
+@@ -0,0 +1,25 @@
 +package io.papermc.paper.command.brigadier;
 +
 +import com.mojang.brigadier.Message;
 +import net.kyori.adventure.text.Component;
 +import net.kyori.adventure.text.serializer.ComponentSerializer;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A component serializer for converting between {@link Message} and {@link Component}.
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface MessageComponentSerializer extends ComponentSerializer<Component, Component, Message> {
 +
@@ -940,7 +945,7 @@ index 0000000000000000000000000000000000000000..57061a3dd738416c2045e641b6080dc3
 +     *
 +     * @return serializer instance
 +     */
-+    static @NotNull MessageComponentSerializer message() {
++    static MessageComponentSerializer message() {
 +        return MessageComponentSerializerHolder.PROVIDER.orElseThrow();
 +    }
 +}
@@ -964,10 +969,10 @@ index 0000000000000000000000000000000000000000..2db12952461c92a64505d6646f6f49f8
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/argument/ArgumentTypes.java b/src/main/java/io/papermc/paper/command/brigadier/argument/ArgumentTypes.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4ef470c70
+index 0000000000000000000000000000000000000000..9abb9ff33672036bb548c688c5661dc8f237aae2
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/argument/ArgumentTypes.java
-@@ -0,0 +1,370 @@
+@@ -0,0 +1,371 @@
 +package io.papermc.paper.command.brigadier.argument;
 +
 +import com.mojang.brigadier.arguments.ArgumentType;
@@ -998,7 +1003,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +import org.bukkit.scoreboard.Criteria;
 +import org.bukkit.scoreboard.DisplaySlot;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +import static io.papermc.paper.command.brigadier.argument.VanillaArgumentProvider.provider;
 +
@@ -1011,6 +1016,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 + * <p>{@link CustomArgumentType} is provided for customizing parsing or result types server-side, while sending the vanilla argument type to the client.</p>
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public final class ArgumentTypes {
 +
 +    /**
@@ -1019,7 +1025,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument that takes one entity
 +     */
-+    public static @NotNull ArgumentType<EntitySelectorArgumentResolver> entity() {
++    public static ArgumentType<EntitySelectorArgumentResolver> entity() {
 +        return provider().entity();
 +    }
 +
@@ -1029,7 +1035,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument that takes multiple entities
 +     */
-+    public static @NotNull ArgumentType<EntitySelectorArgumentResolver> entities() {
++    public static ArgumentType<EntitySelectorArgumentResolver> entities() {
 +        return provider().entities();
 +    }
 +
@@ -1039,7 +1045,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument that takes one player
 +     */
-+    public static @NotNull ArgumentType<PlayerSelectorArgumentResolver> player() {
++    public static ArgumentType<PlayerSelectorArgumentResolver> player() {
 +        return provider().player();
 +    }
 +
@@ -1049,7 +1055,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument that takes multiple players
 +     */
-+    public static @NotNull ArgumentType<PlayerSelectorArgumentResolver> players() {
++    public static ArgumentType<PlayerSelectorArgumentResolver> players() {
 +        return provider().players();
 +    }
 +
@@ -1059,7 +1065,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return player profile argument
 +     */
-+    public static @NotNull ArgumentType<PlayerProfileListResolver> playerProfiles() {
++    public static ArgumentType<PlayerProfileListResolver> playerProfiles() {
 +        return provider().playerProfiles();
 +    }
 +
@@ -1068,7 +1074,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return block position argument
 +     */
-+    public static @NotNull ArgumentType<BlockPositionResolver> blockPosition() {
++    public static ArgumentType<BlockPositionResolver> blockPosition() {
 +        return provider().blockPosition();
 +    }
 +
@@ -1078,7 +1084,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     * @return fine position argument
 +     * @see #finePosition(boolean) to center whole numbers
 +     */
-+    public static @NotNull ArgumentType<FinePositionResolver> finePosition() {
++    public static ArgumentType<FinePositionResolver> finePosition() {
 +        return finePosition(false);
 +    }
 +
@@ -1088,7 +1094,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     * @param centerIntegers if whole numbers should be centered (+0.5)
 +     * @return fine position argument
 +     */
-+    public static @NotNull ArgumentType<FinePositionResolver> finePosition(final boolean centerIntegers) {
++    public static ArgumentType<FinePositionResolver> finePosition(final boolean centerIntegers) {
 +        return provider().finePosition(centerIntegers);
 +    }
 +
@@ -1098,7 +1104,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<BlockState> blockState() {
++    public static ArgumentType<BlockState> blockState() {
 +        return provider().blockState();
 +    }
 +
@@ -1108,7 +1114,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<ItemStack> itemStack() {
++    public static ArgumentType<ItemStack> itemStack() {
 +        return provider().itemStack();
 +    }
 +
@@ -1117,7 +1123,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<ItemStackPredicate> itemPredicate() {
++    public static ArgumentType<ItemStackPredicate> itemPredicate() {
 +        return provider().itemStackPredicate();
 +    }
 +
@@ -1126,7 +1132,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<NamedTextColor> namedColor() {
++    public static ArgumentType<NamedTextColor> namedColor() {
 +        return provider().namedColor();
 +    }
 +
@@ -1135,7 +1141,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<Component> component() {
++    public static ArgumentType<Component> component() {
 +        return provider().component();
 +    }
 +
@@ -1144,7 +1150,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<Style> style() {
++    public static ArgumentType<Style> style() {
 +        return provider().style();
 +    }
 +
@@ -1155,7 +1161,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<SignedMessageResolver> signedMessage() {
++    public static ArgumentType<SignedMessageResolver> signedMessage() {
 +        return provider().signedMessage();
 +    }
 +
@@ -1164,7 +1170,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<DisplaySlot> scoreboardDisplaySlot() {
++    public static ArgumentType<DisplaySlot> scoreboardDisplaySlot() {
 +        return provider().scoreboardDisplaySlot();
 +    }
 +
@@ -1173,7 +1179,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<NamespacedKey> namespacedKey() {
++    public static ArgumentType<NamespacedKey> namespacedKey() {
 +        return provider().namespacedKey();
 +    }
 +
@@ -1183,7 +1189,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     * @return argument
 +     */
 +    // include both key types as we are slowly moving to use adventure's key
-+    public static @NotNull ArgumentType<Key> key() {
++    public static ArgumentType<Key> key() {
 +        return provider().key();
 +    }
 +
@@ -1192,7 +1198,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<IntegerRangeProvider> integerRange() {
++    public static ArgumentType<IntegerRangeProvider> integerRange() {
 +        return provider().integerRange();
 +    }
 +
@@ -1201,7 +1207,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<DoubleRangeProvider> doubleRange() {
++    public static ArgumentType<DoubleRangeProvider> doubleRange() {
 +        return provider().doubleRange();
 +    }
 +
@@ -1210,7 +1216,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<World> world() {
++    public static ArgumentType<World> world() {
 +        return provider().world();
 +    }
 +
@@ -1219,16 +1225,16 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<GameMode> gameMode() {
++    public static ArgumentType<GameMode> gameMode() {
 +        return provider().gameMode();
 +    }
 +
 +    /**
-+     * A argument for getting a heightmap type.
++     * An argument for getting a heightmap type.
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<HeightMap> heightMap() {
++    public static ArgumentType<HeightMap> heightMap() {
 +        return provider().heightMap();
 +    }
 +
@@ -1237,7 +1243,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<UUID> uuid() {
++    public static ArgumentType<UUID> uuid() {
 +        return provider().uuid();
 +    }
 +
@@ -1246,7 +1252,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<Criteria> objectiveCriteria() {
++    public static ArgumentType<Criteria> objectiveCriteria() {
 +        return provider().objectiveCriteria();
 +    }
 +
@@ -1255,7 +1261,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<LookAnchor> entityAnchor() {
++    public static ArgumentType<LookAnchor> entityAnchor() {
 +        return provider().entityAnchor();
 +    }
 +
@@ -1271,7 +1277,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     *
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<Integer> time() {
++    public static ArgumentType<Integer> time() {
 +        return time(0);
 +    }
 +
@@ -1288,7 +1294,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     * @param mintime The minimum time required for this argument.
 +     * @return argument
 +     */
-+    public static @NotNull ArgumentType<Integer> time(final int mintime) {
++    public static ArgumentType<Integer> time(final int mintime) {
 +        return provider().time(mintime);
 +    }
 +
@@ -1298,7 +1304,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     * @return argument
 +     * @see Mirror
 +     */
-+    public static @NotNull ArgumentType<Mirror> templateMirror() {
++    public static ArgumentType<Mirror> templateMirror() {
 +        return provider().templateMirror();
 +    }
 +
@@ -1308,7 +1314,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     * @return argument
 +     * @see StructureRotation
 +     */
-+    public static @NotNull ArgumentType<StructureRotation> templateRotation() {
++    public static ArgumentType<StructureRotation> templateRotation() {
 +        return provider().templateRotation();
 +    }
 +
@@ -1319,7 +1325,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     * @return argument
 +     * @param <T> the registry value type
 +     */
-+    public static <T> @NotNull ArgumentType<T> resource(final @NotNull RegistryKey<T> registryKey) {
++    public static <T> ArgumentType<T> resource(final RegistryKey<T> registryKey) {
 +        return provider().resource(registryKey);
 +    }
 +
@@ -1331,7 +1337,7 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +     * @param <T> the registry value type
 +     * @see RegistryArgumentExtractor#getTypedKey(com.mojang.brigadier.context.CommandContext, RegistryKey, String)
 +     */
-+    public static <T> @NotNull ArgumentType<TypedKey<T>> resourceKey(final @NotNull RegistryKey<T> registryKey) {
++    public static <T> ArgumentType<TypedKey<T>> resourceKey(final RegistryKey<T> registryKey) {
 +        return provider().resourceKey(registryKey);
 +    }
 +
@@ -1340,10 +1346,10 @@ index 0000000000000000000000000000000000000000..f102176791e57d23a148ba79bfc949f4
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/argument/CustomArgumentType.java b/src/main/java/io/papermc/paper/command/brigadier/argument/CustomArgumentType.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..02acac7f9186677d19c0a62095cc3012bc112961
+index 0000000000000000000000000000000000000000..91d40ef0bdbdee3609e33577782c5cce29deda6a
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/argument/CustomArgumentType.java
-@@ -0,0 +1,106 @@
+@@ -0,0 +1,107 @@
 +package io.papermc.paper.command.brigadier.argument;
 +
 +import com.mojang.brigadier.StringReader;
@@ -1355,7 +1361,7 @@ index 0000000000000000000000000000000000000000..02acac7f9186677d19c0a62095cc3012
 +import java.util.Collection;
 +import java.util.concurrent.CompletableFuture;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * An argument type that wraps around a native-to-vanilla argument type.
@@ -1370,6 +1376,7 @@ index 0000000000000000000000000000000000000000..02acac7f9186677d19c0a62095cc3012
 + * @param <N> type with an argument native to vanilla Minecraft (from {@link ArgumentTypes})
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public interface CustomArgumentType<T, N> extends ArgumentType<T> {
 +
 +    /**
@@ -1384,7 +1391,7 @@ index 0000000000000000000000000000000000000000..02acac7f9186677d19c0a62095cc3012
 +     * @throws CommandSyntaxException if an error occurs while parsing
 +     */
 +    @Override
-+    @NotNull T parse(final @NotNull StringReader reader) throws CommandSyntaxException;
++    T parse(final StringReader reader) throws CommandSyntaxException;
 +
 +    /**
 +     * Gets the native type that this argument uses,
@@ -1392,7 +1399,7 @@ index 0000000000000000000000000000000000000000..02acac7f9186677d19c0a62095cc3012
 +     *
 +     * @return native argument type
 +     */
-+    @NotNull ArgumentType<N> getNativeType();
++    ArgumentType<N> getNativeType();
 +
 +    /**
 +     * Cannot be controlled by the server.
@@ -1403,7 +1410,7 @@ index 0000000000000000000000000000000000000000..02acac7f9186677d19c0a62095cc3012
 +     */
 +    @Override
 +    @ApiStatus.NonExtendable
-+    default @NotNull Collection<String> getExamples() {
++    default Collection<String> getExamples() {
 +        return this.getNativeType().getExamples();
 +    }
 +
@@ -1416,7 +1423,7 @@ index 0000000000000000000000000000000000000000..02acac7f9186677d19c0a62095cc3012
 +     * @param <S> context type
 +     */
 +    @Override
-+    default <S> @NotNull CompletableFuture<Suggestions> listSuggestions(final @NotNull CommandContext<S> context, final @NotNull SuggestionsBuilder builder) {
++    default <S> CompletableFuture<Suggestions> listSuggestions(final CommandContext<S> context, final SuggestionsBuilder builder) {
 +        return ArgumentType.super.listSuggestions(context, builder);
 +    }
 +
@@ -1436,7 +1443,7 @@ index 0000000000000000000000000000000000000000..02acac7f9186677d19c0a62095cc3012
 +
 +        @ApiStatus.NonExtendable
 +        @Override
-+        default @NotNull T parse(final @NotNull StringReader reader) throws CommandSyntaxException {
++        default T parse(final StringReader reader) throws CommandSyntaxException {
 +            return this.convert(this.getNativeType().parse(reader));
 +        }
 +
@@ -1447,25 +1454,26 @@ index 0000000000000000000000000000000000000000..02acac7f9186677d19c0a62095cc3012
 +         * @return converted value
 +         * @throws CommandSyntaxException if an exception occurs while parsing
 +         */
-+        @NotNull T convert(@NotNull N nativeType) throws CommandSyntaxException;
++        T convert(N nativeType) throws CommandSyntaxException;
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/argument/RegistryArgumentExtractor.java b/src/main/java/io/papermc/paper/command/brigadier/argument/RegistryArgumentExtractor.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..475266144edf0f7dc4e7939abaf9e1705c4e6461
+index 0000000000000000000000000000000000000000..c6123342df9610a97752030955a43df18e8d0cbd
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/argument/RegistryArgumentExtractor.java
-@@ -0,0 +1,35 @@
+@@ -0,0 +1,36 @@
 +package io.papermc.paper.command.brigadier.argument;
 +
 +import com.mojang.brigadier.context.CommandContext;
 +import io.papermc.paper.registry.RegistryKey;
 +import io.papermc.paper.registry.TypedKey;
-+import org.checkerframework.checker.nullness.qual.NonNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Utilities for extracting registry-related arguments from a {@link CommandContext}.
 + */
++@NullMarked
 +public final class RegistryArgumentExtractor {
 +
 +    /**
@@ -1480,7 +1488,7 @@ index 0000000000000000000000000000000000000000..475266144edf0f7dc4e7939abaf9e170
 +     * @throws IllegalArgumentException if the registry key doesn't match the typed key
 +     */
 +    @SuppressWarnings("unchecked")
-+    public static <T, S> @NonNull TypedKey<T> getTypedKey(final @NonNull CommandContext<S> context, final @NonNull RegistryKey<T> registryKey, final @NonNull String name) {
++    public static <T, S> TypedKey<T> getTypedKey(final CommandContext<S> context, final RegistryKey<T> registryKey, final String name) {
 +        final TypedKey<T> typedKey = context.getArgument(name, TypedKey.class);
 +        if (typedKey.registryKey().equals(registryKey)) {
 +            return typedKey;
@@ -1493,10 +1501,10 @@ index 0000000000000000000000000000000000000000..475266144edf0f7dc4e7939abaf9e170
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/argument/SignedMessageResolver.java b/src/main/java/io/papermc/paper/command/brigadier/argument/SignedMessageResolver.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..159b691e7a1a7066f3e706e80d75ca8f87a3a964
+index 0000000000000000000000000000000000000000..2f2c1729c5d9f1a6b6171c0ed5326b9b631f3c20
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/argument/SignedMessageResolver.java
-@@ -0,0 +1,41 @@
+@@ -0,0 +1,42 @@
 +package io.papermc.paper.command.brigadier.argument;
 +
 +import com.mojang.brigadier.context.CommandContext;
@@ -1505,7 +1513,7 @@ index 0000000000000000000000000000000000000000..159b691e7a1a7066f3e706e80d75ca8f
 +import java.util.concurrent.CompletableFuture;
 +import net.kyori.adventure.chat.SignedMessage;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A resolver for a {@link SignedMessage}
@@ -1513,6 +1521,7 @@ index 0000000000000000000000000000000000000000..159b691e7a1a7066f3e706e80d75ca8f
 + * @see ArgumentTypes#signedMessage()
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface SignedMessageResolver {
 +
@@ -1521,7 +1530,7 @@ index 0000000000000000000000000000000000000000..159b691e7a1a7066f3e706e80d75ca8f
 +     *
 +     * @return string content
 +     */
-+    @NotNull String content();
++    String content();
 +
 +    /**
 +     * Resolves this signed message. This will the {@link CommandContext}
@@ -1535,15 +1544,15 @@ index 0000000000000000000000000000000000000000..159b691e7a1a7066f3e706e80d75ca8f
 +     * @return a completable future for the {@link SignedMessage}
 +     * @throws CommandSyntaxException syntax exception
 +     */
-+    @NotNull CompletableFuture<SignedMessage> resolveSignedMessage(@NotNull String argumentName, @NotNull CommandContext<CommandSourceStack> context) throws CommandSyntaxException;
++    CompletableFuture<SignedMessage> resolveSignedMessage(String argumentName, CommandContext<CommandSourceStack> context) throws CommandSyntaxException;
 +
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/argument/VanillaArgumentProvider.java b/src/main/java/io/papermc/paper/command/brigadier/argument/VanillaArgumentProvider.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..a36a36a46b5d71489e1b3e183d48e6e83721ebdf
+index 0000000000000000000000000000000000000000..4f640bd3e536fb79db54dcedd5807e7de402acef
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/argument/VanillaArgumentProvider.java
-@@ -0,0 +1,107 @@
+@@ -0,0 +1,106 @@
 +package io.papermc.paper.command.brigadier.argument;
 +
 +import com.mojang.brigadier.arguments.ArgumentType;
@@ -1575,12 +1584,11 @@ index 0000000000000000000000000000000000000000..a36a36a46b5d71489e1b3e183d48e6e8
 +import org.bukkit.inventory.ItemStack;
 +import org.bukkit.scoreboard.Criteria;
 +import org.bukkit.scoreboard.DisplaySlot;
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.framework.qual.DefaultQualifier;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
-+@DefaultQualifier(NonNull.class)
++@NullMarked
 +interface VanillaArgumentProvider {
 +
 +    Optional<VanillaArgumentProvider> PROVIDER = ServiceLoader.load(VanillaArgumentProvider.class)
@@ -1714,7 +1722,7 @@ index 0000000000000000000000000000000000000000..06ffff68d2652ef8eb40aa723803c24e
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/argument/range/RangeProvider.java b/src/main/java/io/papermc/paper/command/brigadier/argument/range/RangeProvider.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..651dbf15c155f8d8fef25785300d44752c388b37
+index 0000000000000000000000000000000000000000..af1c01ab0d2146225c54a7766788007314f59328
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/argument/range/RangeProvider.java
 @@ -0,0 +1,22 @@
@@ -1722,7 +1730,7 @@ index 0000000000000000000000000000000000000000..651dbf15c155f8d8fef25785300d4475
 +
 +import com.google.common.collect.Range;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A provider for a range of numbers
@@ -1731,27 +1739,27 @@ index 0000000000000000000000000000000000000000..651dbf15c155f8d8fef25785300d4475
 + * @see io.papermc.paper.command.brigadier.argument.ArgumentTypes
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public sealed interface RangeProvider<T extends Comparable<?>> permits DoubleRangeProvider, IntegerRangeProvider {
 +
 +    /**
 +     * Provides the given range.
 +     * @return range
 +     */
-+    @NotNull
 +    Range<T> range();
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/argument/resolvers/ArgumentResolver.java b/src/main/java/io/papermc/paper/command/brigadier/argument/resolvers/ArgumentResolver.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..dea24d91999f78b77fe85221130d87a54edf004a
+index 0000000000000000000000000000000000000000..60439269d8b1535c779ae8bd008c8f28cc7e4133
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/argument/resolvers/ArgumentResolver.java
-@@ -0,0 +1,26 @@
+@@ -0,0 +1,27 @@
 +package io.papermc.paper.command.brigadier.argument.resolvers;
 +
 +import com.mojang.brigadier.exceptions.CommandSyntaxException;
 +import io.papermc.paper.command.brigadier.CommandSourceStack;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.NotNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * An {@link ArgumentResolver} is capable of resolving
@@ -1761,6 +1769,7 @@ index 0000000000000000000000000000000000000000..dea24d91999f78b77fe85221130d87a5
 + * @see io.papermc.paper.command.brigadier.argument.ArgumentTypes
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface ArgumentResolver<T> {
 +
@@ -1770,7 +1779,7 @@ index 0000000000000000000000000000000000000000..dea24d91999f78b77fe85221130d87a5
 +     * @param sourceStack source stack
 +     * @return resolved
 +     */
-+    @NotNull T resolve(@NotNull CommandSourceStack sourceStack) throws CommandSyntaxException;
++    T resolve(CommandSourceStack sourceStack) throws CommandSyntaxException;
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/argument/resolvers/BlockPositionResolver.java b/src/main/java/io/papermc/paper/command/brigadier/argument/resolvers/BlockPositionResolver.java
 new file mode 100644
@@ -1914,7 +1923,7 @@ index 0000000000000000000000000000000000000000..906ce6eff30ebd9ec3010ce03b471418
 +public interface SelectorArgumentResolver<T> extends ArgumentResolver<T> {
 +}
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
-index 29476a1a82b3526ac03f21011d297d01462d153e..dae4935d8e9f46c52f700927a43a9202dac13df6 100644
+index f70814de0d6c40b2c1c9921b8abdd1162e1d3995..ab6b262cf0d2d17962ed012b2ea7b8f1db8bc576 100644
 --- a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
 @@ -1,9 +1,11 @@
@@ -1928,9 +1937,9 @@ index 29476a1a82b3526ac03f21011d297d01462d153e..dae4935d8e9f46c52f700927a43a9202
 +import io.papermc.paper.plugin.lifecycle.event.registrar.ReloadableRegistrarEvent;
  import org.bukkit.plugin.Plugin;
  import org.jetbrains.annotations.ApiStatus;
- 
-@@ -15,6 +17,13 @@ import org.jetbrains.annotations.ApiStatus;
- @ApiStatus.Experimental
+ import org.jspecify.annotations.NullMarked;
+@@ -17,6 +19,13 @@ import org.jspecify.annotations.NullMarked;
+ @NullMarked
  public final class LifecycleEvents {
  
 +    /**
diff --git a/patches/api/0467-Fix-issues-with-recipe-API.patch b/patches/api/0467-Fix-issues-with-recipe-API.patch
index e20b55ebab..7ca3015001 100644
--- a/patches/api/0467-Fix-issues-with-recipe-API.patch
+++ b/patches/api/0467-Fix-issues-with-recipe-API.patch
@@ -57,18 +57,17 @@ index 1b7b07715067014bf3d35002ae1655793248b426..5bf55b40fbf6ec708f37d90bd0853fe7
  }
 diff --git a/src/main/java/org/bukkit/inventory/EmptyRecipeChoice.java b/src/main/java/org/bukkit/inventory/EmptyRecipeChoice.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..ed0ab6163f47ec843ba4f7ea4a98bb2fa315eaa1
+index 0000000000000000000000000000000000000000..a95ecc97fd6507103f9264a686ec1c061fa725b1
 --- /dev/null
 +++ b/src/main/java/org/bukkit/inventory/EmptyRecipeChoice.java
-@@ -0,0 +1,33 @@
+@@ -0,0 +1,32 @@
 +package org.bukkit.inventory;
 +
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.framework.qual.DefaultQualifier;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
-+@DefaultQualifier(NonNull.class)
++@NullMarked
 +record EmptyRecipeChoice() implements RecipeChoice {
 +
 +    static final RecipeChoice INSTANCE = new EmptyRecipeChoice();
diff --git a/patches/api/0473-Registry-Modification-API.patch b/patches/api/0473-Registry-Modification-API.patch
index 5362f96e91..e6bdf1c69d 100644
--- a/patches/api/0473-Registry-Modification-API.patch
+++ b/patches/api/0473-Registry-Modification-API.patch
@@ -6,29 +6,31 @@ Subject: [PATCH] Registry Modification API
 
 diff --git a/src/main/java/io/papermc/paper/registry/RegistryBuilder.java b/src/main/java/io/papermc/paper/registry/RegistryBuilder.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..6edf300c1d81c1001756141c9efd022ba0e372cd
+index 0000000000000000000000000000000000000000..379e2638aca243bacac777cf59982f9d0e601f3e
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/RegistryBuilder.java
-@@ -0,0 +1,13 @@
+@@ -0,0 +1,15 @@
 +package io.papermc.paper.registry;
 +
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * To be implemented by any type used for modifying registries.
 + *
 + * @param <T> registry value type
 + */
-+@ApiStatus.NonExtendable
 +@ApiStatus.Experimental
++@NullMarked
++@ApiStatus.NonExtendable
 +public interface RegistryBuilder<T> {
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/event/RegistryEntryAddEvent.java b/src/main/java/io/papermc/paper/registry/event/RegistryEntryAddEvent.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..a5d7385eae9dfb88b52aed0e42c09a10ef807385
+index 0000000000000000000000000000000000000000..56468b311e40a6d1aa03c6d31328952b92e95027
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/event/RegistryEntryAddEvent.java
-@@ -0,0 +1,47 @@
+@@ -0,0 +1,48 @@
 +package io.papermc.paper.registry.event;
 +
 +import io.papermc.paper.registry.RegistryBuilder;
@@ -36,8 +38,8 @@ index 0000000000000000000000000000000000000000..a5d7385eae9dfb88b52aed0e42c09a10
 +import io.papermc.paper.registry.tag.Tag;
 +import io.papermc.paper.registry.tag.TagKey;
 +import org.bukkit.Keyed;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Event object for {@link RegistryEventProvider#entryAdd()}. This
@@ -48,6 +50,7 @@ index 0000000000000000000000000000000000000000..a5d7385eae9dfb88b52aed0e42c09a10
 + * @param <B> registry entry builder type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface RegistryEntryAddEvent<T, B extends RegistryBuilder<T>> extends RegistryEvent<T> {
 +
@@ -56,14 +59,14 @@ index 0000000000000000000000000000000000000000..a5d7385eae9dfb88b52aed0e42c09a10
 +     *
 +     * @return the object builder
 +     */
-+    @NonNull B builder();
++    B builder();
 +
 +    /**
 +     * Gets the key for this entry in the registry.
 +     *
 +     * @return the key
 +     */
-+    @NonNull TypedKey<T> key();
++    TypedKey<T> key();
 +
 +    /**
 +     * Gets or creates a tag for the given tag key. This tag
@@ -74,20 +77,20 @@ index 0000000000000000000000000000000000000000..a5d7385eae9dfb88b52aed0e42c09a10
 +     * @return the tag
 +     * @param <V> the tag value type
 +     */
-+    @NonNull <V extends Keyed> Tag<V> getOrCreateTag(@NonNull TagKey<V> tagKey);
++    <V extends Keyed> Tag<V> getOrCreateTag(TagKey<V> tagKey);
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/event/RegistryEvent.java b/src/main/java/io/papermc/paper/registry/event/RegistryEvent.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..498c5920926158e86c2aec2bd2129d5e8b8613a3
+index 0000000000000000000000000000000000000000..3a8643c06d751bf3e4bff4d95b62c675ecdf0f16
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/event/RegistryEvent.java
-@@ -0,0 +1,23 @@
+@@ -0,0 +1,24 @@
 +package io.papermc.paper.registry.event;
 +
 +import io.papermc.paper.plugin.lifecycle.event.LifecycleEvent;
 +import io.papermc.paper.registry.RegistryKey;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Base type for all registry events.
@@ -95,6 +98,7 @@ index 0000000000000000000000000000000000000000..498c5920926158e86c2aec2bd2129d5e
 + * @param <T> registry entry type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface RegistryEvent<T> extends LifecycleEvent {
 +
@@ -103,26 +107,24 @@ index 0000000000000000000000000000000000000000..498c5920926158e86c2aec2bd2129d5e
 +     *
 +     * @return the registry key
 +     */
-+    @NonNull RegistryKey<T> registryKey();
++    RegistryKey<T> registryKey();
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/event/RegistryEventProvider.java b/src/main/java/io/papermc/paper/registry/event/RegistryEventProvider.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..477ed0fd5acc923d429980529876f0dd7dd3a52a
+index 0000000000000000000000000000000000000000..8518e93829318cbfe0eb70f558cb86a7b5742514
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/event/RegistryEventProvider.java
-@@ -0,0 +1,58 @@
+@@ -0,0 +1,57 @@
 +package io.papermc.paper.registry.event;
 +
 +import io.papermc.paper.plugin.bootstrap.BootstrapContext;
 +import io.papermc.paper.plugin.lifecycle.event.handler.LifecycleEventHandler;
-+import io.papermc.paper.plugin.lifecycle.event.handler.configuration.LifecycleEventHandlerConfiguration;
-+import io.papermc.paper.plugin.lifecycle.event.handler.configuration.PrioritizedLifecycleEventHandlerConfiguration;
 +import io.papermc.paper.plugin.lifecycle.event.types.LifecycleEventType;
 +import io.papermc.paper.registry.RegistryBuilder;
 +import io.papermc.paper.registry.RegistryKey;
 +import io.papermc.paper.registry.event.type.RegistryEntryAddEventType;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Provider for registry events for a specific registry.
@@ -137,6 +139,7 @@ index 0000000000000000000000000000000000000000..477ed0fd5acc923d429980529876f0dd
 + * @param <B> registry entry builder type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface RegistryEventProvider<T, B extends RegistryBuilder<T>> {
 +
@@ -149,7 +152,7 @@ index 0000000000000000000000000000000000000000..477ed0fd5acc923d429980529876f0dd
 +     *
 +     * @return the registry entry add event type
 +     */
-+    @NonNull RegistryEntryAddEventType<T, B> entryAdd();
++    RegistryEntryAddEventType<T, B> entryAdd();
 +
 +    /**
 +     * Gets the event type for {@link RegistryFreezeEvent} which is fired just before
@@ -160,21 +163,21 @@ index 0000000000000000000000000000000000000000..477ed0fd5acc923d429980529876f0dd
 +     *
 +     * @return the registry freeze event type
 +     */
-+    LifecycleEventType.@NonNull Prioritizable<BootstrapContext, RegistryFreezeEvent<T, B>> freeze();
++    LifecycleEventType.Prioritizable<BootstrapContext, RegistryFreezeEvent<T, B>> freeze();
 +
 +    /**
 +     * Gets the registry key associated with this event type provider.
 +     *
 +     * @return the registry key
 +     */
-+    @NonNull RegistryKey<T> registryKey();
++    RegistryKey<T> registryKey();
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/event/RegistryEventProviderImpl.java b/src/main/java/io/papermc/paper/registry/event/RegistryEventProviderImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..cfe47c8bd0888db6d00867acfefc8db42ef314aa
+index 0000000000000000000000000000000000000000..8d9afd49077090d30f13b217b71100c73137d120
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/event/RegistryEventProviderImpl.java
-@@ -0,0 +1,30 @@
+@@ -0,0 +1,29 @@
 +package io.papermc.paper.registry.event;
 +
 +import io.papermc.paper.plugin.bootstrap.BootstrapContext;
@@ -182,12 +185,11 @@ index 0000000000000000000000000000000000000000..cfe47c8bd0888db6d00867acfefc8db4
 +import io.papermc.paper.registry.RegistryBuilder;
 +import io.papermc.paper.registry.RegistryKey;
 +import io.papermc.paper.registry.event.type.RegistryEntryAddEventType;
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.framework.qual.DefaultQualifier;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
-+@DefaultQualifier(NonNull.class)
++@NullMarked
 +record RegistryEventProviderImpl<T, B extends RegistryBuilder<T>>(RegistryKey<T> registryKey) implements RegistryEventProvider<T, B> {
 +
 +    static <T, B extends RegistryBuilder<T>> RegistryEventProvider<T, B> create(final RegistryKey<T> registryKey) {
@@ -237,19 +239,21 @@ index 0000000000000000000000000000000000000000..d807bd2f42c98e37a96cf110ad77820d
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/event/RegistryEvents.java b/src/main/java/io/papermc/paper/registry/event/RegistryEvents.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..1f89945be2ed68f52a544f41f7a151b8fdfe113e
+index 0000000000000000000000000000000000000000..91ae9c0d3ec55ce417d4b447bf3d1b0d0c174b5e
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/event/RegistryEvents.java
-@@ -0,0 +1,14 @@
+@@ -0,0 +1,16 @@
 +package io.papermc.paper.registry.event;
 +
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Holds providers for {@link RegistryEntryAddEvent} and {@link RegistryFreezeEvent}
 + * handlers for each applicable registry.
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public final class RegistryEvents {
 +
 +    private RegistryEvents() {
@@ -257,18 +261,18 @@ index 0000000000000000000000000000000000000000..1f89945be2ed68f52a544f41f7a151b8
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/event/RegistryFreezeEvent.java b/src/main/java/io/papermc/paper/registry/event/RegistryFreezeEvent.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..12ec7e794a5047a30354a485acd40fa0f3438eea
+index 0000000000000000000000000000000000000000..59e8ca6c5b7fa0424ad9b2c74545ec53444b5fcb
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/event/RegistryFreezeEvent.java
-@@ -0,0 +1,39 @@
+@@ -0,0 +1,40 @@
 +package io.papermc.paper.registry.event;
 +
 +import io.papermc.paper.registry.RegistryBuilder;
 +import io.papermc.paper.registry.tag.Tag;
 +import io.papermc.paper.registry.tag.TagKey;
 +import org.bukkit.Keyed;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Event object for {@link RegistryEventProvider#freeze()}. This
@@ -279,6 +283,7 @@ index 0000000000000000000000000000000000000000..12ec7e794a5047a30354a485acd40fa0
 + * @param <B> registry entry builder type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface RegistryFreezeEvent<T, B extends RegistryBuilder<T>> extends RegistryEvent<T> {
 +
@@ -287,7 +292,7 @@ index 0000000000000000000000000000000000000000..12ec7e794a5047a30354a485acd40fa0
 +     *
 +     * @return a writable registry
 +     */
-+    @NonNull WritableRegistry<T, B> registry();
++    WritableRegistry<T, B> registry();
 +
 +    /**
 +     * Gets or creates a tag for the given tag key. This tag
@@ -298,21 +303,21 @@ index 0000000000000000000000000000000000000000..12ec7e794a5047a30354a485acd40fa0
 +     * @return the tag
 +     * @param <V> the tag value type
 +     */
-+    @NonNull <V extends Keyed> Tag<V> getOrCreateTag(@NonNull TagKey<V> tagKey);
++    <V extends Keyed> Tag<V> getOrCreateTag(TagKey<V> tagKey);
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/event/WritableRegistry.java b/src/main/java/io/papermc/paper/registry/event/WritableRegistry.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..6de377275097f065c38dd59c6db9704018ac81fc
+index 0000000000000000000000000000000000000000..744f455b14cdc9131497024088da4ca0e8fc39dc
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/event/WritableRegistry.java
-@@ -0,0 +1,27 @@
+@@ -0,0 +1,28 @@
 +package io.papermc.paper.registry.event;
 +
 +import io.papermc.paper.registry.RegistryBuilder;
 +import io.papermc.paper.registry.TypedKey;
 +import java.util.function.Consumer;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A registry which supports registering new objects.
@@ -320,8 +325,9 @@ index 0000000000000000000000000000000000000000..6de377275097f065c38dd59c6db97040
 + * @param <T> registry entry type
 + * @param <B> registry entry builder type
 + */
-+@ApiStatus.NonExtendable
 +@ApiStatus.Experimental
++@NullMarked
++@ApiStatus.NonExtendable
 +public interface WritableRegistry<T, B extends RegistryBuilder<T>> {
 +
 +    /**
@@ -331,28 +337,29 @@ index 0000000000000000000000000000000000000000..6de377275097f065c38dd59c6db97040
 +     * @param key the entry's key (must be unique from others)
 +     * @param value a consumer for the entry's builder
 +     */
-+    void register(@NonNull TypedKey<T> key, @NonNull Consumer<? super B> value);
++    void register(TypedKey<T> key, Consumer<? super B> value);
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/event/type/RegistryEntryAddConfiguration.java b/src/main/java/io/papermc/paper/registry/event/type/RegistryEntryAddConfiguration.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..c5b484ee5f4a0f283a8d46f5490afac4b58b06be
+index 0000000000000000000000000000000000000000..d9bde790f74982c6cd5870aee35fec8a0c49fc83
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/event/type/RegistryEntryAddConfiguration.java
-@@ -0,0 +1,42 @@
+@@ -0,0 +1,43 @@
 +package io.papermc.paper.registry.event.type;
 +
 +import io.papermc.paper.plugin.bootstrap.BootstrapContext;
 +import io.papermc.paper.plugin.lifecycle.event.handler.configuration.PrioritizedLifecycleEventHandlerConfiguration;
 +import io.papermc.paper.registry.TypedKey;
 +import java.util.function.Predicate;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.Contract;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Specific configuration for {@link io.papermc.paper.registry.event.RegistryEntryAddEvent}s.
 + *
 + * @param <T> registry entry type
 + */
++@NullMarked
 +public interface RegistryEntryAddConfiguration<T> extends PrioritizedLifecycleEventHandlerConfiguration<BootstrapContext> {
 +
 +    /**
@@ -362,7 +369,7 @@ index 0000000000000000000000000000000000000000..c5b484ee5f4a0f283a8d46f5490afac4
 +     * @return this configuration
 +     */
 +    @Contract(value = "_ -> this", mutates = "this")
-+    default @NonNull RegistryEntryAddConfiguration<T> filter(final @NonNull TypedKey<T> key) {
++    default RegistryEntryAddConfiguration<T> filter(final TypedKey<T> key) {
 +        return this.filter(key::equals);
 +    }
 +
@@ -373,20 +380,20 @@ index 0000000000000000000000000000000000000000..c5b484ee5f4a0f283a8d46f5490afac4
 +     * @return this configuration
 +     */
 +    @Contract(value = "_ -> this", mutates = "this")
-+    @NonNull RegistryEntryAddConfiguration<T> filter(@NonNull Predicate<TypedKey<T>> filter);
++    RegistryEntryAddConfiguration<T> filter(Predicate<TypedKey<T>> filter);
 +
 +    @Override
-+    @NonNull RegistryEntryAddConfiguration<T> priority(int priority);
++    RegistryEntryAddConfiguration<T> priority(int priority);
 +
 +    @Override
-+    @NonNull RegistryEntryAddConfiguration<T> monitor();
++    RegistryEntryAddConfiguration<T> monitor();
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/event/type/RegistryEntryAddEventType.java b/src/main/java/io/papermc/paper/registry/event/type/RegistryEntryAddEventType.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..f4d4ebf6cbed1b4a9955ceb2d0586782181d97e5
+index 0000000000000000000000000000000000000000..93447ef58933f37fe12c4507c9a0b233be4c6c0b
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/event/type/RegistryEntryAddEventType.java
-@@ -0,0 +1,18 @@
+@@ -0,0 +1,20 @@
 +package io.papermc.paper.registry.event.type;
 +
 +import io.papermc.paper.plugin.bootstrap.BootstrapContext;
@@ -394,6 +401,7 @@ index 0000000000000000000000000000000000000000..f4d4ebf6cbed1b4a9955ceb2d0586782
 +import io.papermc.paper.registry.RegistryBuilder;
 +import io.papermc.paper.registry.event.RegistryEntryAddEvent;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Lifecycle event type for {@link RegistryEntryAddEvent}s.
@@ -402,15 +410,16 @@ index 0000000000000000000000000000000000000000..f4d4ebf6cbed1b4a9955ceb2d0586782
 + * @param <B> registry entry builder type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface RegistryEntryAddEventType<T, B extends RegistryBuilder<T>> extends LifecycleEventType<BootstrapContext, RegistryEntryAddEvent<T, B>, RegistryEntryAddConfiguration<T>> {
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/set/RegistryKeySet.java b/src/main/java/io/papermc/paper/registry/set/RegistryKeySet.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..b891101b43148f63c96b7dd611914c85d7b29dbf
+index 0000000000000000000000000000000000000000..d5a5e332abc861d8509a5df7b57319f72e6b5449
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/set/RegistryKeySet.java
-@@ -0,0 +1,50 @@
+@@ -0,0 +1,51 @@
 +package io.papermc.paper.registry.set;
 +
 +import io.papermc.paper.registry.TypedKey;
@@ -418,11 +427,12 @@ index 0000000000000000000000000000000000000000..b891101b43148f63c96b7dd611914c85
 +import java.util.Iterator;
 +import org.bukkit.Keyed;
 +import org.bukkit.Registry;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public non-sealed interface RegistryKeySet<T extends Keyed> extends Iterable<TypedKey<T>>, RegistrySet<T> { // TODO remove Keyed
 +
@@ -436,7 +446,7 @@ index 0000000000000000000000000000000000000000..b891101b43148f63c96b7dd611914c85
 +     *
 +     * @return the keys
 +     */
-+    @NonNull @Unmodifiable Collection<TypedKey<T>> values();
++    @Unmodifiable Collection<TypedKey<T>> values();
 +
 +    /**
 +     * Resolve this set into a collection of values. Prefer using
@@ -446,7 +456,7 @@ index 0000000000000000000000000000000000000000..b891101b43148f63c96b7dd611914c85
 +     * @return the resolved values
 +     * @see RegistryKeySet#values()
 +     */
-+    @NonNull @Unmodifiable Collection<T> resolve(final @NonNull Registry<T> registry);
++    @Unmodifiable Collection<T> resolve(final Registry<T> registry);
 +
 +    /**
 +     * Checks if this set contains the value with the given key.
@@ -454,19 +464,19 @@ index 0000000000000000000000000000000000000000..b891101b43148f63c96b7dd611914c85
 +     * @param valueKey the key to check
 +     * @return true if the value is in this set
 +     */
-+    boolean contains(@NonNull TypedKey<T> valueKey);
++    boolean contains(TypedKey<T> valueKey);
 +
 +    @Override
-+    default @NonNull Iterator<TypedKey<T>> iterator() {
++    default Iterator<TypedKey<T>> iterator() {
 +        return this.values().iterator();
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/set/RegistryKeySetImpl.java b/src/main/java/io/papermc/paper/registry/set/RegistryKeySetImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..c712181ad4c6a9d00bc04f8a48515a388c692f48
+index 0000000000000000000000000000000000000000..fe4a0817d7ac4a9f958a6156d6ae3ac1c96f58cd
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/set/RegistryKeySetImpl.java
-@@ -0,0 +1,53 @@
+@@ -0,0 +1,52 @@
 +package io.papermc.paper.registry.set;
 +
 +import com.google.common.base.Preconditions;
@@ -480,20 +490,19 @@ index 0000000000000000000000000000000000000000..c712181ad4c6a9d00bc04f8a48515a38
 +import org.bukkit.Keyed;
 +import org.bukkit.NamespacedKey;
 +import org.bukkit.Registry;
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.framework.qual.DefaultQualifier;
 +import org.jetbrains.annotations.ApiStatus;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +@ApiStatus.Internal
-+@DefaultQualifier(NonNull.class)
-+record RegistryKeySetImpl<T extends Keyed>(RegistryKey<T> registryKey, List<TypedKey<T>> values) implements RegistryKeySet<T> { // TODO remove Keyed
++@NullMarked
++record RegistryKeySetImpl<T extends @Nullable Keyed>(RegistryKey<T> registryKey, List<TypedKey<T>> values) implements RegistryKeySet<T> { // TODO remove Keyed
 +
 +    static <T extends Keyed> RegistryKeySet<T> create(final RegistryKey<T> registryKey, final Iterable<? extends T> values) { // TODO remove Keyed
 +        final Registry<T> registry = RegistryAccess.registryAccess().getRegistry(registryKey);
 +        final ArrayList<TypedKey<T>> keys = new ArrayList<>();
 +        for (final T value : values) {
-+            final @Nullable NamespacedKey key = registry.getKey(value);
++            final NamespacedKey key = registry.getKey(value);
 +            Preconditions.checkArgument(key != null, value + " does not have a key in " + registryKey);
 +            keys.add(TypedKey.create(registryKey, key));
 +        }
@@ -513,7 +522,7 @@ index 0000000000000000000000000000000000000000..c712181ad4c6a9d00bc04f8a48515a38
 +    public Collection<T> resolve(final Registry<T> registry) {
 +        final List<T> values = new ArrayList<>(this.values.size());
 +        for (final TypedKey<T> key : this.values) {
-+            final @Nullable T value = registry.get(key.key());
++            final T value = registry.get(key.key());
 +            Preconditions.checkState(value != null, "Trying to access unbound TypedKey: " + key);
 +            values.add(value);
 +        }
@@ -522,10 +531,10 @@ index 0000000000000000000000000000000000000000..c712181ad4c6a9d00bc04f8a48515a38
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/set/RegistrySet.java b/src/main/java/io/papermc/paper/registry/set/RegistrySet.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..108df480e16131781a52c7bbba2ca6581e4c1ca1
+index 0000000000000000000000000000000000000000..c6fdeb05242418d20472aeed8cb61bfe937911c8
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/set/RegistrySet.java
-@@ -0,0 +1,112 @@
+@@ -0,0 +1,113 @@
 +package io.papermc.paper.registry.set;
 +
 +import com.google.common.collect.Lists;
@@ -533,9 +542,9 @@ index 0000000000000000000000000000000000000000..108df480e16131781a52c7bbba2ca658
 +import io.papermc.paper.registry.TypedKey;
 +import io.papermc.paper.registry.tag.Tag;
 +import org.bukkit.Keyed;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents a collection tied to a registry.
@@ -553,6 +562,7 @@ index 0000000000000000000000000000000000000000..108df480e16131781a52c7bbba2ca658
 + * @param <T> registry value type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public sealed interface RegistrySet<T> permits RegistryKeySet, RegistryValueSet {
 +
 +    // TODO uncomment when direct holder sets need to be exposed to the API
@@ -566,7 +576,7 @@ index 0000000000000000000000000000000000000000..108df480e16131781a52c7bbba2ca658
 +    //  * @param <T> the type of the values
 +    //  */
 +    // @Contract(value = "_, _ -> new", pure = true)
-+    // static <T> @NonNull RegistryValueSet<T> valueSet(final @NonNull RegistryKey<T> registryKey, final @NonNull Iterable<? extends T> values) {
++    // static <T> RegistryValueSet<T> valueSet(final RegistryKey<T> registryKey, final Iterable<? extends T> values) {
 +    //     return RegistryValueSetImpl.create(registryKey, values);
 +    // }
 +
@@ -584,7 +594,7 @@ index 0000000000000000000000000000000000000000..108df480e16131781a52c7bbba2ca658
 +     * @throws IllegalArgumentException if the registry isn't available yet or if any value doesn't have a key in that registry
 +     */
 +    @Contract(value = "_, _ -> new", pure = true)
-+    static <T extends Keyed> @NonNull RegistryKeySet<T> keySetFromValues(final @NonNull RegistryKey<T> registryKey, final @NonNull Iterable<? extends T> values) { // TODO remove Keyed
++    static <T extends Keyed> RegistryKeySet<T> keySetFromValues(final RegistryKey<T> registryKey, final Iterable<? extends T> values) { // TODO remove Keyed
 +        return RegistryKeySetImpl.create(registryKey, values);
 +    }
 +
@@ -597,7 +607,7 @@ index 0000000000000000000000000000000000000000..108df480e16131781a52c7bbba2ca658
 +     * @param <T> the type of the values
 +     */
 +    @SafeVarargs
-+    static <T extends Keyed> RegistryKeySet<T> keySet(final @NonNull RegistryKey<T> registryKey, final @NonNull TypedKey<T> @NonNull... keys) { // TODO remove Keyed
++    static <T extends Keyed> RegistryKeySet<T> keySet(final RegistryKey<T> registryKey, final TypedKey<T>... keys) { // TODO remove Keyed
 +        return keySet(registryKey, Lists.newArrayList(keys));
 +    }
 +
@@ -611,7 +621,7 @@ index 0000000000000000000000000000000000000000..108df480e16131781a52c7bbba2ca658
 +     */
 +    @SuppressWarnings("BoundedWildcard")
 +    @Contract(value = "_, _ -> new", pure = true)
-+    static <T extends Keyed> @NonNull RegistryKeySet<T> keySet(final @NonNull RegistryKey<T> registryKey, final @NonNull Iterable<TypedKey<T>> keys) { // TODO remove Keyed
++    static <T extends Keyed> RegistryKeySet<T> keySet(final RegistryKey<T> registryKey, final Iterable<TypedKey<T>> keys) { // TODO remove Keyed
 +        return new RegistryKeySetImpl<>(registryKey, Lists.newArrayList(keys));
 +    }
 +
@@ -620,7 +630,7 @@ index 0000000000000000000000000000000000000000..108df480e16131781a52c7bbba2ca658
 +     *
 +     * @return the registry key
 +     */
-+    @NonNull RegistryKey<T> registryKey();
++    RegistryKey<T> registryKey();
 +
 +    /**
 +     * Get the size of this set.
@@ -640,17 +650,17 @@ index 0000000000000000000000000000000000000000..108df480e16131781a52c7bbba2ca658
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/set/RegistryValueSet.java b/src/main/java/io/papermc/paper/registry/set/RegistryValueSet.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..58e2e42737d48b243854466eb7f7d3a844a86b6e
+index 0000000000000000000000000000000000000000..9f7761535c30c376dad64678fa2ee24bbb041e06
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/set/RegistryValueSet.java
-@@ -0,0 +1,34 @@
+@@ -0,0 +1,35 @@
 +package io.papermc.paper.registry.set;
 +
 +import java.util.Collection;
 +import java.util.Iterator;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A collection of anonymous values relating to a registry. These
@@ -659,6 +669,7 @@ index 0000000000000000000000000000000000000000..58e2e42737d48b243854466eb7f7d3a8
 + * @param <T> registry value type
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public sealed interface RegistryValueSet<T> extends Iterable<T>, RegistrySet<T> permits RegistryValueSetImpl {
 +
 +    @Override
@@ -671,27 +682,29 @@ index 0000000000000000000000000000000000000000..58e2e42737d48b243854466eb7f7d3a8
 +     *
 +     * @return the values
 +     */
-+    @NonNull @Unmodifiable Collection<T> values();
++    @Unmodifiable Collection<T> values();
 +
 +    @Override
-+    default @NonNull Iterator<T> iterator() {
++    default Iterator<T> iterator() {
 +        return this.values().iterator();
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/set/RegistryValueSetImpl.java b/src/main/java/io/papermc/paper/registry/set/RegistryValueSetImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..4ce5b26a1fcaae7b28ac8ed3c25014b66c266318
+index 0000000000000000000000000000000000000000..1bcc6b4b9ff0090570d4f39a49e10e1fa03edb7d
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/set/RegistryValueSetImpl.java
-@@ -0,0 +1,18 @@
+@@ -0,0 +1,20 @@
 +package io.papermc.paper.registry.set;
 +
 +import com.google.common.collect.Lists;
 +import io.papermc.paper.registry.RegistryKey;
 +import java.util.List;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
++@NullMarked
 +record RegistryValueSetImpl<T>(RegistryKey<T> registryKey, List<T> values) implements RegistryValueSet<T> {
 +
 +    RegistryValueSetImpl {
@@ -704,16 +717,16 @@ index 0000000000000000000000000000000000000000..4ce5b26a1fcaae7b28ac8ed3c25014b6
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/tag/Tag.java b/src/main/java/io/papermc/paper/registry/tag/Tag.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..ae374f68ef9baa16ed90c371f1622de0c0159873
+index 0000000000000000000000000000000000000000..245eb1074ce2930e4d9ff42a5df49004d08bbac2
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/tag/Tag.java
-@@ -0,0 +1,25 @@
+@@ -0,0 +1,26 @@
 +package io.papermc.paper.registry.tag;
 +
 +import io.papermc.paper.registry.set.RegistryKeySet;
 +import org.bukkit.Keyed;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A named {@link RegistryKeySet} which are created
@@ -724,6 +737,7 @@ index 0000000000000000000000000000000000000000..ae374f68ef9baa16ed90c371f1622de0
 + * @see org.bukkit.Registry#getTag(TagKey)
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +public interface Tag<T extends Keyed> extends RegistryKeySet<T> { // TODO remove Keyed
 +
 +    /**
@@ -731,24 +745,25 @@ index 0000000000000000000000000000000000000000..ae374f68ef9baa16ed90c371f1622de0
 +     *
 +     * @return the tag key identifier
 +     */
-+    @NonNull TagKey<T> tagKey();
++    TagKey<T> tagKey();
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/tag/TagKey.java b/src/main/java/io/papermc/paper/registry/tag/TagKey.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..a49d328e95f7fda6567ee6c4f5f1878a2c187277
+index 0000000000000000000000000000000000000000..f84d95b29fd2c0a52d2769fa9d3e2326ebc8aa3f
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/tag/TagKey.java
-@@ -0,0 +1,32 @@
+@@ -0,0 +1,33 @@
 +package io.papermc.paper.registry.tag;
 +
 +import io.papermc.paper.registry.RegistryKey;
 +import net.kyori.adventure.key.Key;
 +import net.kyori.adventure.key.Keyed;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Experimental
++@NullMarked
 +public sealed interface TagKey<T> extends Keyed permits TagKeyImpl {
 +
 +    /**
@@ -760,7 +775,7 @@ index 0000000000000000000000000000000000000000..a49d328e95f7fda6567ee6c4f5f1878a
 +     * @param <T> the registry value type
 +     */
 +    @Contract(value = "_, _ -> new", pure = true)
-+    static <T> @NonNull TagKey<T> create(final @NonNull RegistryKey<T> registryKey, final @NonNull Key key) {
++    static <T> TagKey<T> create(final RegistryKey<T> registryKey, final Key key) {
 +        return new TagKeyImpl<>(registryKey, key);
 +    }
 +
@@ -769,24 +784,23 @@ index 0000000000000000000000000000000000000000..a49d328e95f7fda6567ee6c4f5f1878a
 +     *
 +     * @return the registry key
 +     */
-+    @NonNull RegistryKey<T> registryKey();
++    RegistryKey<T> registryKey();
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/tag/TagKeyImpl.java b/src/main/java/io/papermc/paper/registry/tag/TagKeyImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..5fde17e97eddcd1d01ee39694c9159d0ff2a09e3
+index 0000000000000000000000000000000000000000..bf49125acc8a0508bf59674bba3ed3505ee9481a
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/tag/TagKeyImpl.java
-@@ -0,0 +1,17 @@
+@@ -0,0 +1,16 @@
 +package io.papermc.paper.registry.tag;
 +
 +import io.papermc.paper.registry.RegistryKey;
 +import net.kyori.adventure.key.Key;
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.framework.qual.DefaultQualifier;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
-+@DefaultQualifier(NonNull.class)
++@NullMarked
 +record TagKeyImpl<T>(RegistryKey<T> registryKey, Key key) implements TagKey<T> {
 +
 +    @Override
diff --git a/patches/api/0474-Introduce-registry-entry-and-builders.patch b/patches/api/0474-Introduce-registry-entry-and-builders.patch
index e2e4937863..446b1f78f2 100644
--- a/patches/api/0474-Introduce-registry-entry-and-builders.patch
+++ b/patches/api/0474-Introduce-registry-entry-and-builders.patch
@@ -5,10 +5,10 @@ Subject: [PATCH] Introduce registry entry and builders
 
 
 diff --git a/src/main/java/io/papermc/paper/registry/RegistryKey.java b/src/main/java/io/papermc/paper/registry/RegistryKey.java
-index 1e2765d296decbb3e61b8434e78b5e0214f8fee0..5e580649578d25f567b0f7d40bcdc68f62701f0a 100644
+index 8410d7213370f01cbedbf7fac29bac96f150c49a..d8716f855806471728c35b3ec34efb808a5146cf 100644
 --- a/src/main/java/io/papermc/paper/registry/RegistryKey.java
 +++ b/src/main/java/io/papermc/paper/registry/RegistryKey.java
-@@ -77,9 +77,10 @@ public sealed interface RegistryKey<T> extends Keyed permits RegistryKeyImpl {
+@@ -79,9 +79,10 @@ public sealed interface RegistryKey<T> extends Keyed permits RegistryKeyImpl {
      @ApiStatus.Internal
      RegistryKey<BlockType> BLOCK = create("block");
      /**
@@ -23,7 +23,7 @@ index 1e2765d296decbb3e61b8434e78b5e0214f8fee0..5e580649578d25f567b0f7d40bcdc68f
       * Built-in registry for cat variants.
 diff --git a/src/main/java/io/papermc/paper/registry/data/EnchantmentRegistryEntry.java b/src/main/java/io/papermc/paper/registry/data/EnchantmentRegistryEntry.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe188db6d12f
+index 0000000000000000000000000000000000000000..d0d19a4bb2ba0e92710861b106777a428bdc5ad9
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/data/EnchantmentRegistryEntry.java
 @@ -0,0 +1,332 @@
@@ -40,18 +40,18 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +import org.bukkit.enchantments.Enchantment;
 +import org.bukkit.inventory.EquipmentSlotGroup;
 +import org.bukkit.inventory.ItemType;
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.checker.nullness.qual.Nullable;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
-+import org.jetbrains.annotations.NotNull;
 +import org.jetbrains.annotations.Range;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * A data-centric version-specific registry entry for the {@link Enchantment} type.
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface EnchantmentRegistryEntry {
 +
@@ -61,14 +61,14 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +     *
 +     * @return the description component.
 +     */
-+    @NonNull Component description();
++    Component description();
 +
 +    /**
 +     * Provides the registry key set referencing the items this enchantment is supported on.
 +     *
 +     * @return the registry key set.
 +     */
-+    @NonNull RegistryKeySet<ItemType> supportedItems();
++    RegistryKeySet<ItemType> supportedItems();
 +
 +    /**
 +     * Provides the registry key set referencing the item types this enchantment can be applied to when
@@ -106,7 +106,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +     * @see <a href="https://minecraft.wiki/w/Enchanting/Levels">https://minecraft.wiki/w/Enchanting/Levels</a> for
 +     * examplary costs.
 +     */
-+    @NonNull EnchantmentCost minimumCost();
++    EnchantmentCost minimumCost();
 +
 +    /**
 +     * Provides the maximum cost allowed to enchant an item with this enchantment.
@@ -117,7 +117,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +     * @see <a href="https://minecraft.wiki/w/Enchanting/Levels">https://minecraft.wiki/w/Enchanting/Levels</a> for
 +     * examplary costs.
 +     */
-+    @NonNull EnchantmentCost maximumCost();
++    EnchantmentCost maximumCost();
 +
 +    /**
 +     * Provides the cost of applying this enchantment using an anvil.
@@ -140,7 +140,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +     * @return a list of equipment slot groups.
 +     * @see Enchantment#getActiveSlotGroups()
 +     */
-+    @NonNull @Unmodifiable List<EquipmentSlotGroup> activeSlots();
++    @Unmodifiable List<EquipmentSlotGroup> activeSlots();
 +
 +    /**
 +     * Provides the registry key set of enchantments that this enchantment is exclusive with.
@@ -150,7 +150,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +     *
 +     * @return a registry set of enchantments exclusive to this one.
 +     */
-+    @NonNull RegistryKeySet<Enchantment> exclusiveWith();
++    RegistryKeySet<Enchantment> exclusiveWith();
 +
 +    /**
 +     * A mutable builder for the {@link EnchantmentRegistryEntry} plugins may change in applicable registry events.
@@ -179,7 +179,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * @return this builder.
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder description(@NonNull Component description);
++        Builder description(Component description);
 +
 +        /**
 +         * Configures the set of supported items this enchantment can be applied on. This
@@ -195,7 +195,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * @see io.papermc.paper.registry.event.RegistryFreezeEvent#getOrCreateTag(TagKey)
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder supportedItems(@NonNull RegistryKeySet<ItemType> supportedItems);
++        Builder supportedItems(RegistryKeySet<ItemType> supportedItems);
 +
 +        /**
 +         * Configures a set of item types this enchantment can naturally be applied to, when enchanting in an
@@ -216,7 +216,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * @see io.papermc.paper.registry.event.RegistryFreezeEvent#getOrCreateTag(TagKey)
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder primaryItems(@Nullable RegistryKeySet<ItemType> primaryItems);
++        Builder primaryItems(@Nullable RegistryKeySet<ItemType> primaryItems);
 +
 +        /**
 +         * Configures the weight of this enchantment used by the weighted random when selecting enchantments.
@@ -226,7 +226,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * @see <a href="https://minecraft.wiki/w/Enchanting">https://minecraft.wiki/w/Enchanting</a> for examplary weights.
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder weight(@Range(from = 1, to = 1024) int weight);
++        Builder weight(@Range(from = 1, to = 1024) int weight);
 +
 +        /**
 +         * Configures the maximum level this enchantment can have when applied.
@@ -235,7 +235,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * @return this builder.
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder maxLevel(@Range(from = 1, to = 255) int maxLevel);
++        Builder maxLevel(@Range(from = 1, to = 255) int maxLevel);
 +
 +        /**
 +         * Configures the minimum cost needed to enchant an item with this enchantment.
@@ -248,7 +248,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * examplary costs.
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder minimumCost(@NotNull EnchantmentCost minimumCost);
++        Builder minimumCost(EnchantmentCost minimumCost);
 +
 +        /**
 +         * Configures the maximum cost to enchant an item with this enchantment.
@@ -261,7 +261,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * examplary costs.
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder maximumCost(@NotNull EnchantmentCost maximumCost);
++        Builder maximumCost(EnchantmentCost maximumCost);
 +
 +        /**
 +         * Configures the cost of applying this enchantment using an anvil.
@@ -275,7 +275,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * @see Enchantment#getAnvilCost()
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder anvilCost(@Range(from = 0, to = Integer.MAX_VALUE) int anvilCost);
++        Builder anvilCost(@Range(from = 0, to = Integer.MAX_VALUE) int anvilCost);
 +
 +        /**
 +         * Configures the list of slot groups this enchantment may be active in.
@@ -288,7 +288,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * @see Enchantment#getActiveSlotGroups()
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        default @NonNull Builder activeSlots(final @NonNull EquipmentSlotGroup @NonNull... activeSlots) {
++        default Builder activeSlots(final EquipmentSlotGroup... activeSlots) {
 +            return this.activeSlots(List.of(activeSlots));
 +        }
 +
@@ -303,7 +303,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * @see Enchantment#getActiveSlotGroups()
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder activeSlots(@NonNull Iterable<@NonNull EquipmentSlotGroup> activeSlots);
++        Builder activeSlots(Iterable<EquipmentSlotGroup> activeSlots);
 +
 +        /**
 +         * Configures the registry key set of enchantments that this enchantment is exclusive with.
@@ -319,7 +319,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +         * @see io.papermc.paper.registry.event.RegistryFreezeEvent#getOrCreateTag(TagKey)
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder exclusiveWith(@NonNull RegistryKeySet<Enchantment> exclusiveWith);
++        Builder exclusiveWith(RegistryKeySet<Enchantment> exclusiveWith);
 +    }
 +
 +    /**
@@ -345,7 +345,7 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +        /**
 +         * Creates a new enchantment cost instance based on the passed values.
 +         *
-+         * @param baseCost               the base cost of the enchantment cost as returned by {@link #baseCost()}
++         * @param baseCost the base cost of the enchantment cost as returned by {@link #baseCost()}
 +         * @param additionalPerLevelCost the additional cost per level, as returned by {@link #additionalPerLevelCost()}
 +         * @return the created instance.
 +         */
@@ -361,23 +361,24 @@ index 0000000000000000000000000000000000000000..6c7d8b98103909428bb4dcf14825fe18
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/data/GameEventRegistryEntry.java b/src/main/java/io/papermc/paper/registry/data/GameEventRegistryEntry.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..a59620816f8795fc0e585f969741d1940340673a
+index 0000000000000000000000000000000000000000..980fe12b75258b51cc2498590cadb9de80805b1f
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/registry/data/GameEventRegistryEntry.java
-@@ -0,0 +1,48 @@
+@@ -0,0 +1,49 @@
 +package io.papermc.paper.registry.data;
 +
 +import io.papermc.paper.registry.RegistryBuilder;
 +import org.bukkit.GameEvent;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
 +import org.jetbrains.annotations.Range;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * A data-centric version-specific registry entry for the {@link GameEvent} type.
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface GameEventRegistryEntry {
 +
@@ -410,7 +411,7 @@ index 0000000000000000000000000000000000000000..a59620816f8795fc0e585f969741d194
 +         * @see GameEvent#getRange()
 +         */
 +        @Contract(value = "_ -> this", mutates = "this")
-+        @NonNull Builder range(@Range(from = 0, to = Integer.MAX_VALUE) int range);
++        Builder range(@Range(from = 0, to = Integer.MAX_VALUE) int range);
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/registry/data/package-info.java b/src/main/java/io/papermc/paper/registry/data/package-info.java
@@ -429,10 +430,10 @@ index 0000000000000000000000000000000000000000..4f8f536f437c5f483ac7bce393e664fd
 + */
 +package io.papermc.paper.registry.data;
 diff --git a/src/main/java/io/papermc/paper/registry/event/RegistryEvents.java b/src/main/java/io/papermc/paper/registry/event/RegistryEvents.java
-index 1f89945be2ed68f52a544f41f7a151b8fdfe113e..b32ae215e976bcfcdd86b03037de61b3d896f57c 100644
+index 91ae9c0d3ec55ce417d4b447bf3d1b0d0c174b5e..1c8e77c7243cfedef6c4d1491cf98e6ec8f1690f 100644
 --- a/src/main/java/io/papermc/paper/registry/event/RegistryEvents.java
 +++ b/src/main/java/io/papermc/paper/registry/event/RegistryEvents.java
-@@ -1,7 +1,14 @@
+@@ -1,8 +1,15 @@
  package io.papermc.paper.registry.event;
  
 +import io.papermc.paper.registry.RegistryKey;
@@ -441,14 +442,15 @@ index 1f89945be2ed68f52a544f41f7a151b8fdfe113e..b32ae215e976bcfcdd86b03037de61b3
 +import org.bukkit.GameEvent;
 +import org.bukkit.enchantments.Enchantment;
  import org.jetbrains.annotations.ApiStatus;
+ import org.jspecify.annotations.NullMarked;
  
 +import static io.papermc.paper.registry.event.RegistryEventProviderImpl.create;
 +
  /**
   * Holds providers for {@link RegistryEntryAddEvent} and {@link RegistryFreezeEvent}
   * handlers for each applicable registry.
-@@ -9,6 +16,9 @@ import org.jetbrains.annotations.ApiStatus;
- @ApiStatus.Experimental
+@@ -11,6 +18,9 @@ import org.jspecify.annotations.NullMarked;
+ @NullMarked
  public final class RegistryEvents {
  
 +    public static final RegistryEventProvider<GameEvent, GameEventRegistryEntry.Builder> GAME_EVENT = create(RegistryKey.GAME_EVENT);
diff --git a/patches/api/0476-Make-a-PDC-view-accessible-directly-from-ItemStack.patch b/patches/api/0476-Make-a-PDC-view-accessible-directly-from-ItemStack.patch
index 042b9e8600..0c48106249 100644
--- a/patches/api/0476-Make-a-PDC-view-accessible-directly-from-ItemStack.patch
+++ b/patches/api/0476-Make-a-PDC-view-accessible-directly-from-ItemStack.patch
@@ -6,10 +6,10 @@ Subject: [PATCH] Make a PDC view accessible directly from ItemStack
 
 diff --git a/src/main/java/io/papermc/paper/persistence/PersistentDataContainerView.java b/src/main/java/io/papermc/paper/persistence/PersistentDataContainerView.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea119e202bf
+index 0000000000000000000000000000000000000000..061ffc1f050a950e041ceef217b5f335e3cd0af1
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/persistence/PersistentDataContainerView.java
-@@ -0,0 +1,167 @@
+@@ -0,0 +1,160 @@
 +package io.papermc.paper.persistence;
 +
 +import java.util.Set;
@@ -18,15 +18,17 @@ index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea1
 +import org.bukkit.persistence.PersistentDataContainer;
 +import org.bukkit.persistence.PersistentDataHolder;
 +import org.bukkit.persistence.PersistentDataType;
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.checker.nullness.qual.Nullable;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * This represents a view of a persistent data container. No
 + * methods on this interface mutate the container.
++ *
 + * @see PersistentDataContainer
 + */
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface PersistentDataContainerView {
 +
@@ -52,14 +54,12 @@ index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea1
 +     * @param type the type the primative stored value has to match
 +     * @param <P> the generic type of the stored primitive
 +     * @param <C> the generic type of the eventually created complex object
-+     *
 +     * @return if a value with the provided key and type exists
-+     *
 +     * @throws IllegalArgumentException if the key to look up is null
 +     * @throws IllegalArgumentException if the type to cast the found object to is
 +     * null
 +     */
-+    <P, C> boolean has(@NonNull NamespacedKey key, @NonNull PersistentDataType<P, C> type);
++    <P, C> boolean has(NamespacedKey key, PersistentDataType<P, C> type);
 +
 +    /**
 +     * Returns if the persistent metadata provider has metadata registered matching
@@ -73,12 +73,10 @@ index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea1
 +     * namespace.
 +     *
 +     * @param key the key the value is stored under
-+     *
 +     * @return if a value with the provided key exists
-+     *
 +     * @throws IllegalArgumentException if the key to look up is null
 +     */
-+    boolean has(@NonNull NamespacedKey key);
++    boolean has(NamespacedKey key);
 +
 +    /**
 +     * Returns the metadata value that is stored on the
@@ -88,10 +86,8 @@ index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea1
 +     * @param type the type the value must have and will be casted to
 +     * @param <P> the generic type of the stored primitive
 +     * @param <C> the generic type of the eventually created complex object
-+     *
 +     * @return the value or {@code null} if no value was mapped under the given
 +     * value
-+     *
 +     * @throws IllegalArgumentException if the key to look up is null
 +     * @throws IllegalArgumentException if the type to cast the found object to is
 +     * null
@@ -101,7 +97,7 @@ index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea1
 +     * the {@link
 +     * PersistentDataType#getPrimitiveType()}
 +     */
-+    <P, C> @Nullable C get(@NonNull NamespacedKey key, @NonNull PersistentDataType<P, C> type);
++    <P, C> @Nullable C get(NamespacedKey key, PersistentDataType<P, C> type);
 +
 +    /**
 +     * Returns the metadata value that is stored on the
@@ -114,10 +110,8 @@ index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea1
 +     * the provided key
 +     * @param <P> the generic type of the stored primitive
 +     * @param <C> the generic type of the eventually created complex object
-+     *
 +     * @return the value or the default value if no value was mapped under the
 +     * given key
-+     *
 +     * @throws IllegalArgumentException if the key to look up is null
 +     * @throws IllegalArgumentException if the type to cast the found object to is
 +     * null
@@ -126,18 +120,18 @@ index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea1
 +     * @throws IllegalArgumentException if no suitable adapter was found for
 +     * the {@link PersistentDataType#getPrimitiveType()}
 +     */
-+    <P, C> @NonNull C getOrDefault(@NonNull NamespacedKey key, @NonNull PersistentDataType<P, C> type, @NonNull C defaultValue);
++    <P, C> C getOrDefault(NamespacedKey key, PersistentDataType<P, C> type, C defaultValue);
 +
 +    /**
 +     * Get the set of keys present on this {@link PersistentDataContainer}
 +     * instance.
-+     *
++     * <p>
 +     * Any changes made to the returned set will not be reflected on the
 +     * instance.
 +     *
 +     * @return the key set
 +     */
-+    @NonNull Set<NamespacedKey> getKeys();
++    Set<NamespacedKey> getKeys();
 +
 +    /**
 +     * Returns if the container instance is empty, therefore has no entries
@@ -154,19 +148,18 @@ index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea1
 +     * This method only copies custom object keys. Existing tags, like the display
 +     * name, will not be copied as the values are stored using your namespace.
 +     *
-+     * @param other   the container to copy to
++     * @param other the container to copy to
 +     * @param replace whether to replace any matching values in the target container
-+     *
 +     * @throws IllegalArgumentException if the other container is null
 +     */
-+    void copyTo(@NonNull PersistentDataContainer other, boolean replace);
++    void copyTo(PersistentDataContainer other, boolean replace);
 +
 +    /**
 +     * Returns the adapter context this tag container uses.
 +     *
 +     * @return the tag context
 +     */
-+    @NonNull PersistentDataAdapterContext getAdapterContext();
++    PersistentDataAdapterContext getAdapterContext();
 +
 +    /**
 +     * Serialize this {@link PersistentDataContainer} instance to a
@@ -175,23 +168,24 @@ index 0000000000000000000000000000000000000000..4a4949fde3f03e2ea9d2dde245f7dea1
 +     * @return a binary representation of this container
 +     * @throws java.io.IOException if we fail to write this container to a byte array
 +     */
-+    byte @NonNull [] serializeToBytes() throws java.io.IOException;
++    byte[] serializeToBytes() throws java.io.IOException;
 +}
 diff --git a/src/main/java/io/papermc/paper/persistence/PersistentDataViewHolder.java b/src/main/java/io/papermc/paper/persistence/PersistentDataViewHolder.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..9789916f949374bfb50da535b076180700f7ae73
+index 0000000000000000000000000000000000000000..05bc2ac326fb58ea429cee825520e70f7f211f0d
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/persistence/PersistentDataViewHolder.java
-@@ -0,0 +1,23 @@
+@@ -0,0 +1,24 @@
 +package io.papermc.paper.persistence;
 +
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * The {@link PersistentDataViewHolder} interface defines an object that can view
 + * custom persistent data on it.
 + */
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface PersistentDataViewHolder {
 +
@@ -204,10 +198,10 @@ index 0000000000000000000000000000000000000000..9789916f949374bfb50da535b0761807
 +     *
 +     * @return the persistent data container view
 +     */
-+    @NonNull PersistentDataContainerView getPersistentDataContainer();
++    PersistentDataContainerView getPersistentDataContainer();
 +}
 diff --git a/src/main/java/org/bukkit/inventory/ItemStack.java b/src/main/java/org/bukkit/inventory/ItemStack.java
-index 4fe68a22576933676271f841a5af0ee45b90216f..b3abe3bde05d4a360e31e490bff8a859dc2bd4a6 100644
+index 6fc8bddfcabca8c363e0d9f958f0ce7bc39099f1..7f63a3a37eb06049bd5de10466c6dd96cb5dd4ee 100644
 --- a/src/main/java/org/bukkit/inventory/ItemStack.java
 +++ b/src/main/java/org/bukkit/inventory/ItemStack.java
 @@ -27,7 +27,7 @@ import org.jetbrains.annotations.Nullable;
diff --git a/patches/api/0483-Leashable-API.patch b/patches/api/0483-Leashable-API.patch
index e5b1a4857d..e37174d499 100644
--- a/patches/api/0483-Leashable-API.patch
+++ b/patches/api/0483-Leashable-API.patch
@@ -6,19 +6,20 @@ Subject: [PATCH] Leashable API
 
 diff --git a/src/main/java/io/papermc/paper/entity/Leashable.java b/src/main/java/io/papermc/paper/entity/Leashable.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..7402bab20db0ebcac5b2d492ad002ecf9669caad
+index 0000000000000000000000000000000000000000..7e687535d1a622ddf25e3ece387dbfd5b7a49e83
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/entity/Leashable.java
-@@ -0,0 +1,36 @@
+@@ -0,0 +1,37 @@
 +package io.papermc.paper.entity;
 +
 +import org.bukkit.entity.Entity;
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.checker.nullness.qual.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
 +/**
 + * Represents an entity that can be leashed.
 + */
++@NullMarked
 +public interface Leashable extends Entity {
 +
 +    /**
@@ -34,7 +35,7 @@ index 0000000000000000000000000000000000000000..7402bab20db0ebcac5b2d492ad002ecf
 +     * @return the entity holding the leash
 +     * @throws IllegalStateException if not currently leashed
 +     */
-+    @NonNull Entity getLeashHolder() throws IllegalStateException;
++    Entity getLeashHolder() throws IllegalStateException;
 +
 +    /**
 +     * Sets the leash on this entity to be held by the supplied entity.
diff --git a/patches/api/0486-Add-FeatureFlag-API.patch b/patches/api/0486-Add-FeatureFlag-API.patch
index 1d1e64605f..af03d9a748 100644
--- a/patches/api/0486-Add-FeatureFlag-API.patch
+++ b/patches/api/0486-Add-FeatureFlag-API.patch
@@ -6,17 +6,17 @@ Subject: [PATCH] Add FeatureFlag API
 
 diff --git a/src/main/java/io/papermc/paper/world/flag/FeatureDependant.java b/src/main/java/io/papermc/paper/world/flag/FeatureDependant.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..0fda065100c17ee00060df16467c0f7f98984ea7
+index 0000000000000000000000000000000000000000..f5633319c64bf19cf07e2b9a1cac2dd1d11ab70b
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/world/flag/FeatureDependant.java
-@@ -0,0 +1,27 @@
+@@ -0,0 +1,28 @@
 +package io.papermc.paper.world.flag;
 +
 +import java.util.Set;
 +import org.bukkit.FeatureFlag;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Implemented by types in built-in registries that are controlled by {@link FeatureFlag FeatureFlags}.
@@ -24,6 +24,7 @@ index 0000000000000000000000000000000000000000..0fda065100c17ee00060df16467c0f7f
 + * @apiNote When a type that currently implements this interface transitions to being data-drive, this
 + * interface will be removed from that type in the following major version.
 + */
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface FeatureDependant {
 +
@@ -33,16 +34,16 @@ index 0000000000000000000000000000000000000000..0fda065100c17ee00060df16467c0f7f
 +     *
 +     * @return the immutable set of feature flags
 +     */
-+    default @Unmodifiable @NonNull Set<FeatureFlag> requiredFeatures() {
++    default @Unmodifiable Set<FeatureFlag> requiredFeatures() {
 +        return FeatureFlagProvider.provider().requiredFeatures(this);
 +    }
 +}
 diff --git a/src/main/java/io/papermc/paper/world/flag/FeatureFlagProvider.java b/src/main/java/io/papermc/paper/world/flag/FeatureFlagProvider.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..f64cbee35fd3c6fe7b5f7391f6d118166d26dc18
+index 0000000000000000000000000000000000000000..388e70628f88d8ee0749a43f82b228453e25d5d0
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/world/flag/FeatureFlagProvider.java
-@@ -0,0 +1,19 @@
+@@ -0,0 +1,21 @@
 +package io.papermc.paper.world.flag;
 +
 +import java.util.Optional;
@@ -50,7 +51,9 @@ index 0000000000000000000000000000000000000000..f64cbee35fd3c6fe7b5f7391f6d11816
 +import java.util.Set;
 +import org.bukkit.FeatureFlag;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
++@NullMarked
 +@ApiStatus.Internal
 +interface FeatureFlagProvider {
 +
@@ -64,22 +67,23 @@ index 0000000000000000000000000000000000000000..f64cbee35fd3c6fe7b5f7391f6d11816
 +}
 diff --git a/src/main/java/io/papermc/paper/world/flag/FeatureFlagSetHolder.java b/src/main/java/io/papermc/paper/world/flag/FeatureFlagSetHolder.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..c4432ee20872eeb127852159cf89ed00809fb00e
+index 0000000000000000000000000000000000000000..0955699df65ccbb8711cfa48f0b34d5a8805f1af
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/world/flag/FeatureFlagSetHolder.java
-@@ -0,0 +1,31 @@
+@@ -0,0 +1,32 @@
 +package io.papermc.paper.world.flag;
 +
 +import java.util.Set;
 +import org.bukkit.FeatureFlag;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Implemented by types that hold {@link FeatureFlag FeatureFlags} like
 + * {@link org.bukkit.generator.WorldInfo} and {@link org.bukkit.RegionAccessor}.
 + */
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface FeatureFlagSetHolder {
 +
@@ -88,7 +92,7 @@ index 0000000000000000000000000000000000000000..c4432ee20872eeb127852159cf89ed00
 +     *
 +     * @return true if enabled
 +     */
-+    default boolean isEnabled(final @NonNull FeatureDependant featureDependant) {
++    default boolean isEnabled(final FeatureDependant featureDependant) {
 +        return this.getFeatureFlags().containsAll(featureDependant.requiredFeatures());
 +    }
 +
@@ -97,7 +101,7 @@ index 0000000000000000000000000000000000000000..c4432ee20872eeb127852159cf89ed00
 +     *
 +     * @return all enabled {@link FeatureFlag FeatureFlags}
 +     */
-+    @Unmodifiable @NonNull Set<FeatureFlag> getFeatureFlags();
++    @Unmodifiable Set<FeatureFlag> getFeatureFlags();
 +}
 diff --git a/src/main/java/org/bukkit/FeatureFlag.java b/src/main/java/org/bukkit/FeatureFlag.java
 index 026b1832bcd163ab89668c991bf002e608e36aef..b5e87480b6a1d064547e4e608f3d402825931a00 100644
@@ -181,20 +185,19 @@ index 026b1832bcd163ab89668c991bf002e608e36aef..b5e87480b6a1d064547e4e608f3d4028
  }
 diff --git a/src/main/java/org/bukkit/FeatureFlagImpl.java b/src/main/java/org/bukkit/FeatureFlagImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..a33517dbd69021fde8246836720b6247800ee43c
+index 0000000000000000000000000000000000000000..5a43f65f633dc9a1a0ba7dba0c15488375427444
 --- /dev/null
 +++ b/src/main/java/org/bukkit/FeatureFlagImpl.java
-@@ -0,0 +1,29 @@
+@@ -0,0 +1,27 @@
 +package org.bukkit;
 +
 +import java.util.HashSet;
 +import java.util.Set;
-+import org.checkerframework.checker.nullness.qual.NonNull;
-+import org.checkerframework.framework.qual.DefaultQualifier;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +@ApiStatus.Internal
-+@DefaultQualifier(NonNull.class)
++@NullMarked
 +record FeatureFlagImpl(NamespacedKey key) implements FeatureFlag {
 +
 +    static final Set<FeatureFlag> ALL_FLAGS = new HashSet<>();
@@ -205,7 +208,6 @@ index 0000000000000000000000000000000000000000..a33517dbd69021fde8246836720b6247
 +    }
 +
 +    @ApiStatus.Internal
-+    @DefaultQualifier(NonNull.class)
 +    record Deprecated(NamespacedKey key) implements FeatureFlag {
 +
 +        @Override
diff --git a/patches/api/0487-Tag-Lifecycle-Events.patch b/patches/api/0487-Tag-Lifecycle-Events.patch
index d9fdf676e8..29aaad5c34 100644
--- a/patches/api/0487-Tag-Lifecycle-Events.patch
+++ b/patches/api/0487-Tag-Lifecycle-Events.patch
@@ -5,10 +5,10 @@ Subject: [PATCH] Tag Lifecycle Events
 
 
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventTypeProvider.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventTypeProvider.java
-index 3b17f056d162dd42cae0d33cbbb22fece82fe525..a52ab9e09420768d89385c881fb7a4c424e5b8d6 100644
+index e15e09c2a4d3f43db6a0159fa8af6179362ea8d6..ece6b72c5a93c1faf3de971ee97a1f40d8c4e4e9 100644
 --- a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventTypeProvider.java
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEventTypeProvider.java
-@@ -19,4 +19,6 @@ interface LifecycleEventTypeProvider {
+@@ -21,4 +21,6 @@ interface LifecycleEventTypeProvider {
      <O extends LifecycleEventOwner, E extends LifecycleEvent> LifecycleEventType.Monitorable<O, E> monitor(String name, Class<? extends O> ownerType);
  
      <O extends LifecycleEventOwner, E extends LifecycleEvent> LifecycleEventType.Prioritizable<O, E> prioritized(String name, Class<? extends O> ownerType);
@@ -16,10 +16,10 @@ index 3b17f056d162dd42cae0d33cbbb22fece82fe525..a52ab9e09420768d89385c881fb7a4c4
 +    TagEventTypeProvider tagProvider();
  }
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
-index dae4935d8e9f46c52f700927a43a9202dac13df6..720fe2546015838708ce794c291ca187cf7bca9c 100644
+index ab6b262cf0d2d17962ed012b2ea7b8f1db8bc576..b65c5fd5443cef80989d55bf684191f849afa0e7 100644
 --- a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/LifecycleEvents.java
-@@ -24,6 +24,12 @@ public final class LifecycleEvents {
+@@ -26,6 +26,12 @@ public final class LifecycleEvents {
       */
      public static final LifecycleEventType.Prioritizable<LifecycleEventOwner, ReloadableRegistrarEvent<Commands>> COMMANDS = prioritized("commands", LifecycleEventOwner.class);
  
@@ -34,10 +34,10 @@ index dae4935d8e9f46c52f700927a43a9202dac13df6..720fe2546015838708ce794c291ca187
      static <E extends LifecycleEvent> LifecycleEventType.Monitorable<Plugin, E> plugin(final String name) {
 diff --git a/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/TagEventTypeProvider.java b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/TagEventTypeProvider.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..61c5f6cc6986193eab596ee55e1a414afcf4fbd1
+index 0000000000000000000000000000000000000000..843ce7848c6f3c94b1d8609922bb256138bdb4d4
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/plugin/lifecycle/event/types/TagEventTypeProvider.java
-@@ -0,0 +1,40 @@
+@@ -0,0 +1,41 @@
 +package io.papermc.paper.plugin.lifecycle.event.types;
 +
 +import io.papermc.paper.plugin.bootstrap.BootstrapContext;
@@ -45,8 +45,8 @@ index 0000000000000000000000000000000000000000..61c5f6cc6986193eab596ee55e1a414a
 +import io.papermc.paper.registry.RegistryKey;
 +import io.papermc.paper.tag.PostFlattenTagRegistrar;
 +import io.papermc.paper.tag.PreFlattenTagRegistrar;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Provides event types for tag registration.
@@ -55,6 +55,7 @@ index 0000000000000000000000000000000000000000..61c5f6cc6986193eab596ee55e1a414a
 + * @see PostFlattenTagRegistrar
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface TagEventTypeProvider {
 +
@@ -66,7 +67,7 @@ index 0000000000000000000000000000000000000000..61c5f6cc6986193eab596ee55e1a414a
 +     * @param <T> the type of value in the tag
 +     * @see PreFlattenTagRegistrar
 +     */
-+    <T> LifecycleEventType.@NonNull Prioritizable<BootstrapContext, ReloadableRegistrarEvent<PreFlattenTagRegistrar<T>>> preFlatten(@NonNull RegistryKey<T> registryKey);
++    <T> LifecycleEventType.Prioritizable<BootstrapContext, ReloadableRegistrarEvent<PreFlattenTagRegistrar<T>>> preFlatten(RegistryKey<T> registryKey);
 +
 +    /**
 +     * Get a prioritizable, reloadable registrar event for tags after they are flattened.
@@ -76,14 +77,14 @@ index 0000000000000000000000000000000000000000..61c5f6cc6986193eab596ee55e1a414a
 +     * @param <T> the type of value in the tag
 +     * @see PostFlattenTagRegistrar
 +     */
-+    <T> LifecycleEventType.@NonNull Prioritizable<BootstrapContext, ReloadableRegistrarEvent<PostFlattenTagRegistrar<T>>> postFlatten(@NonNull RegistryKey<T> registryKey);
++    <T> LifecycleEventType.Prioritizable<BootstrapContext, ReloadableRegistrarEvent<PostFlattenTagRegistrar<T>>> postFlatten(RegistryKey<T> registryKey);
 +}
 diff --git a/src/main/java/io/papermc/paper/tag/PostFlattenTagRegistrar.java b/src/main/java/io/papermc/paper/tag/PostFlattenTagRegistrar.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563eddf5e9e
+index 0000000000000000000000000000000000000000..22db9446ca12e7c8e6381e322649ef574d877359
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/tag/PostFlattenTagRegistrar.java
-@@ -0,0 +1,103 @@
+@@ -0,0 +1,104 @@
 +package io.papermc.paper.tag;
 +
 +import io.papermc.paper.plugin.lifecycle.event.registrar.Registrar;
@@ -92,10 +93,10 @@ index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563
 +import io.papermc.paper.registry.tag.TagKey;
 +import java.util.Collection;
 +import java.util.Map;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Registrar for tags after they have been flattened. Flattened
@@ -110,7 +111,7 @@ index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563
 + * class YourBootstrapClass implements PluginBootstrap {
 + *
 + *     @Override
-+ *     public void bootstrap(@NotNull BootstrapContext context) {
++ *     public void bootstrap(BootstrapContext context) {
 + *         LifecycleEventManager<BootstrapContext> manager = context.getLifecycleManager();
 + *         manager.registerEventHandler(LifecycleEvents.TAGS.postFlatten(RegistryKey.ENCHANTMENT), event -> {
 + *             final PostFlattenTagRegistrar<Enchantment> registrar = event.registrar();
@@ -127,6 +128,7 @@ index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563
 + * @see PreFlattenTagRegistrar
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface PostFlattenTagRegistrar<T> extends Registrar {
 +
@@ -135,7 +137,7 @@ index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563
 +     *
 +     * @return the registry key
 +     */
-+    @NonNull RegistryKey<T> registryKey();
++    RegistryKey<T> registryKey();
 +
 +    /**
 +     * Get a copy of all tags currently held in this registrar.
@@ -143,7 +145,7 @@ index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563
 +     * @return an immutable map of all tags
 +     */
 +    @Contract(value = "-> new", pure = true)
-+    @Unmodifiable @NonNull Map<TagKey<T>, Collection<TypedKey<T>>> getAllTags();
++    @Unmodifiable Map<TagKey<T>, Collection<TypedKey<T>>> getAllTags();
 +
 +    /**
 +     * Checks if this registrar has a tag with the given key.
@@ -152,7 +154,7 @@ index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563
 +     * @return true if the tag exists, false otherwise
 +     */
 +    @Contract(pure = true)
-+    boolean hasTag(@NonNull TagKey<T> tagKey);
++    boolean hasTag(TagKey<T> tagKey);
 +
 +    /**
 +     * Get the tag with the given key. Use {@link #hasTag(TagKey)} to check
@@ -164,7 +166,7 @@ index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563
 +     * @see #hasTag(TagKey)
 +     */
 +    @Contract(value = "_ -> new", pure = true)
-+    @Unmodifiable @NonNull Collection<TypedKey<T>> getTag(@NonNull TagKey<T> tagKey);
++    @Unmodifiable Collection<TypedKey<T>> getTag(TagKey<T> tagKey);
 +
 +    /**
 +     * Adds values to the given tag. If the tag does not exist, it will be created.
@@ -174,7 +176,7 @@ index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563
 +     * @see #setTag(TagKey, Collection)
 +     */
 +    @Contract(mutates = "this")
-+    void addToTag(@NonNull TagKey<T> tagKey, @NonNull Collection<TypedKey<T>> values);
++    void addToTag(TagKey<T> tagKey, Collection<TypedKey<T>> values);
 +
 +    /**
 +     * Sets the values of the given tag. If the tag does not exist, it will be created.
@@ -185,14 +187,14 @@ index 0000000000000000000000000000000000000000..32d79dac18c402c3d95edb642eef1563
 +     * @see #addToTag(TagKey, Collection)
 +     */
 +    @Contract(mutates = "this")
-+    void setTag(@NonNull TagKey<T> tagKey, @NonNull Collection<TypedKey<T>> values);
++    void setTag(TagKey<T> tagKey, Collection<TypedKey<T>> values);
 +}
 diff --git a/src/main/java/io/papermc/paper/tag/PreFlattenTagRegistrar.java b/src/main/java/io/papermc/paper/tag/PreFlattenTagRegistrar.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce2fafa796
+index 0000000000000000000000000000000000000000..8d8a00e4d965bf2e76b1924f5dc8973c6469e3a1
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/tag/PreFlattenTagRegistrar.java
-@@ -0,0 +1,102 @@
+@@ -0,0 +1,103 @@
 +package io.papermc.paper.tag;
 +
 +import io.papermc.paper.plugin.lifecycle.event.registrar.Registrar;
@@ -201,10 +203,10 @@ index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce
 +import java.util.Collection;
 +import java.util.List;
 +import java.util.Map;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
 +import org.jetbrains.annotations.Unmodifiable;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Registrar for tags before they are flattened. Flattened
@@ -218,7 +220,7 @@ index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce
 + * class YourBootstrapClass implements PluginBootstrap {
 + *
 + *     @Override
-+ *     public void bootstrap(@NotNull BootstrapContext context) {
++ *     public void bootstrap(BootstrapContext context) {
 + *         LifecycleEventManager<BootstrapContext> manager = context.getLifecycleManager();
 + *         manager.registerEventHandler(LifecycleEvents.TAGS.preFlatten(RegistryKey.ITEM), event -> {
 + *             final PreFlattenTagRegistrar<ItemType> registrar = event.registrar();
@@ -235,6 +237,7 @@ index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce
 + * @see PostFlattenTagRegistrar
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface PreFlattenTagRegistrar<T> extends Registrar {
 +
@@ -243,7 +246,7 @@ index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce
 +     *
 +     * @return the registry key
 +     */
-+    @NonNull RegistryKey<T> registryKey();
++    RegistryKey<T> registryKey();
 +
 +    /**
 +     * Get a copy of all tags currently held in this registrar.
@@ -251,7 +254,7 @@ index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce
 +     * @return an immutable map of all tags
 +     */
 +    @Contract(value = "-> new", pure = true)
-+    @Unmodifiable @NonNull Map<TagKey<T>, Collection<TagEntry<T>>> getAllTags();
++    @Unmodifiable Map<TagKey<T>, Collection<TagEntry<T>>> getAllTags();
 +
 +    /**
 +     * Checks if this registrar has a tag with the given key.
@@ -260,7 +263,7 @@ index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce
 +     * @return true if the tag exists, false otherwise
 +     */
 +    @Contract(pure = true)
-+    boolean hasTag(@NonNull TagKey<T> tagKey);
++    boolean hasTag(TagKey<T> tagKey);
 +
 +    /**
 +     * Get the tag with the given key. Use {@link #hasTag(TagKey)} to check
@@ -272,7 +275,7 @@ index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce
 +     * @see #hasTag(TagKey)
 +     */
 +    @Contract(value = "_ -> new", pure = true)
-+    @Unmodifiable @NonNull List<TagEntry<T>> getTag(@NonNull TagKey<T> tagKey);
++    @Unmodifiable List<TagEntry<T>> getTag(TagKey<T> tagKey);
 +
 +    /**
 +     * Adds entries to the given tag. If the tag does not exist, it will be created.
@@ -282,7 +285,7 @@ index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce
 +     * @see #setTag(TagKey, Collection)
 +     */
 +    @Contract(mutates = "this")
-+    void addToTag(@NonNull TagKey<T> tagKey, @NonNull Collection<TagEntry<T>> entries);
++    void addToTag(TagKey<T> tagKey, Collection<TagEntry<T>> entries);
 +
 +    /**
 +     * Sets the entries of the given tag. If the tag does not exist, it will be created.
@@ -293,22 +296,22 @@ index 0000000000000000000000000000000000000000..44f7a9d3c2734fb00d11890ece9dc4ce
 +     * @see #addToTag(TagKey, Collection)
 +     */
 +    @Contract(mutates = "this")
-+    void setTag(@NonNull TagKey<T> tagKey, @NonNull Collection<TagEntry<T>> entries);
++    void setTag(TagKey<T> tagKey, Collection<TagEntry<T>> entries);
 +}
 diff --git a/src/main/java/io/papermc/paper/tag/TagEntry.java b/src/main/java/io/papermc/paper/tag/TagEntry.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..436b701f1231354a78a9e0ab04ffd9097343ecfc
+index 0000000000000000000000000000000000000000..efa52b387eb6ab476c3a785b46e7647a1da4a343
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/tag/TagEntry.java
-@@ -0,0 +1,89 @@
+@@ -0,0 +1,90 @@
 +package io.papermc.paper.tag;
 +
 +import io.papermc.paper.registry.TypedKey;
 +import io.papermc.paper.registry.tag.TagKey;
 +import net.kyori.adventure.key.Keyed;
-+import org.checkerframework.checker.nullness.qual.NonNull;
 +import org.jetbrains.annotations.ApiStatus;
 +import org.jetbrains.annotations.Contract;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * An entry is a pre-flattened tag. Represents
@@ -318,6 +321,7 @@ index 0000000000000000000000000000000000000000..436b701f1231354a78a9e0ab04ffd909
 + * @see PreFlattenTagRegistrar
 + */
 +@ApiStatus.Experimental
++@NullMarked
 +@ApiStatus.NonExtendable
 +public interface TagEntry<T> extends Keyed {
 +
@@ -329,7 +333,7 @@ index 0000000000000000000000000000000000000000..436b701f1231354a78a9e0ab04ffd909
 +     * @param <T> the type of value
 +     */
 +    @Contract(value = "_ -> new", pure = true)
-+    static <T> @NonNull TagEntry<T> valueEntry(final @NonNull TypedKey<T> entryKey) {
++    static <T> TagEntry<T> valueEntry(final TypedKey<T> entryKey) {
 +        return valueEntry(entryKey, true);
 +    }
 +
@@ -342,7 +346,7 @@ index 0000000000000000000000000000000000000000..436b701f1231354a78a9e0ab04ffd909
 +     * @param <T> the type of value
 +     */
 +    @Contract(value = "_, _ -> new", pure = true)
-+    static <T> @NonNull TagEntry<T> valueEntry(final @NonNull TypedKey<T> entryKey, final boolean isRequired) {
++    static <T> TagEntry<T> valueEntry(final TypedKey<T> entryKey, final boolean isRequired) {
 +        return new TagEntryImpl<>(entryKey.key(), false, isRequired);
 +    }
 +
@@ -354,7 +358,7 @@ index 0000000000000000000000000000000000000000..436b701f1231354a78a9e0ab04ffd909
 +     * @param <T> the type of value
 +     */
 +    @Contract(value = "_ -> new", pure = true)
-+    static <T> @NonNull TagEntry<T> tagEntry(final @NonNull TagKey<T> tagKey) {
++    static <T> TagEntry<T> tagEntry(final TagKey<T> tagKey) {
 +        return tagEntry(tagKey, true);
 +    }
 +
@@ -367,7 +371,7 @@ index 0000000000000000000000000000000000000000..436b701f1231354a78a9e0ab04ffd909
 +     * @param <T> the type of value
 +     */
 +    @Contract(value = "_, _ -> new", pure = true)
-+    static <T> @NonNull TagEntry<T> tagEntry(final @NonNull TagKey<T> tagKey, final boolean isRequired) {
++    static <T> TagEntry<T> tagEntry(final TagKey<T> tagKey, final boolean isRequired) {
 +        return new TagEntryImpl<>(tagKey.key(), true, isRequired);
 +    }
 +
@@ -392,15 +396,17 @@ index 0000000000000000000000000000000000000000..436b701f1231354a78a9e0ab04ffd909
 +}
 diff --git a/src/main/java/io/papermc/paper/tag/TagEntryImpl.java b/src/main/java/io/papermc/paper/tag/TagEntryImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..c0ffd2b9f814d92d0d9b370dfa7e352f1241f614
+index 0000000000000000000000000000000000000000..8d46a330ca47d9ca0ed2c35e696841f7a387f7cd
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/tag/TagEntryImpl.java
-@@ -0,0 +1,8 @@
+@@ -0,0 +1,10 @@
 +package io.papermc.paper.tag;
 +
 +import net.kyori.adventure.key.Key;
 +import org.jetbrains.annotations.ApiStatus;
++import org.jspecify.annotations.NullMarked;
 +
++@NullMarked
 +@ApiStatus.Internal
 +record TagEntryImpl<T>(Key key, boolean isTag, boolean isRequired) implements TagEntry<T> {
 +}
diff --git a/patches/api/0489-create-TileStateInventoryHolder.patch b/patches/api/0489-create-TileStateInventoryHolder.patch
index 107bd2fd51..eafc877be4 100644
--- a/patches/api/0489-create-TileStateInventoryHolder.patch
+++ b/patches/api/0489-create-TileStateInventoryHolder.patch
@@ -7,20 +7,21 @@ a missing interface to centralize getSnapshotInventory methods
 
 diff --git a/src/main/java/io/papermc/paper/block/TileStateInventoryHolder.java b/src/main/java/io/papermc/paper/block/TileStateInventoryHolder.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..170a215465678024f8842e1f9f3132f8e45f213d
+index 0000000000000000000000000000000000000000..59868ac52854f2e9c628f6c72ecd9fafcce15f9f
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/block/TileStateInventoryHolder.java
-@@ -0,0 +1,38 @@
+@@ -0,0 +1,39 @@
 +package io.papermc.paper.block;
 +
 +import org.bukkit.block.TileState;
 +import org.bukkit.inventory.BlockInventoryHolder;
 +import org.bukkit.inventory.Inventory;
-+import org.checkerframework.checker.nullness.qual.NonNull;
++import org.jspecify.annotations.NullMarked;
 +
 +/**
 + * Represents a {@link TileState} block that has an inventory.
 + */
++@NullMarked
 +public interface TileStateInventoryHolder extends TileState, BlockInventoryHolder {
 +
 +    /**
@@ -35,7 +36,7 @@ index 0000000000000000000000000000000000000000..170a215465678024f8842e1f9f3132f8
 +     * @return the inventory
 +     */
 +    @Override
-+    @NonNull Inventory getInventory();
++    Inventory getInventory();
 +
 +    /**
 +     * Gets the captured inventory snapshot of this container.
@@ -47,7 +48,7 @@ index 0000000000000000000000000000000000000000..170a215465678024f8842e1f9f3132f8
 +     *
 +     * @return the captured inventory snapshot
 +     */
-+    @NonNull Inventory getSnapshotInventory();
++    Inventory getSnapshotInventory();
 +}
 diff --git a/src/main/java/org/bukkit/block/ChiseledBookshelf.java b/src/main/java/org/bukkit/block/ChiseledBookshelf.java
 index 1cc5c2021cf1241b090b28697e09bcd36595ab13..92f41d00dcb40fee18305502783e12d87a1c5c94 100644
diff --git a/patches/server/0580-More-CommandBlock-API.patch b/patches/server/0580-More-CommandBlock-API.patch
index 16cf3ee3d7..5fa4fa81e1 100644
--- a/patches/server/0580-More-CommandBlock-API.patch
+++ b/patches/server/0580-More-CommandBlock-API.patch
@@ -6,41 +6,42 @@ Subject: [PATCH] More CommandBlock API
 
 diff --git a/src/main/java/io/papermc/paper/commands/PaperCommandBlockHolder.java b/src/main/java/io/papermc/paper/commands/PaperCommandBlockHolder.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..0b42306f17bf8850a13a51067c2d19e7583187e5
+index 0000000000000000000000000000000000000000..0463aef1c8be238b00e73907bde927f1522a46ce
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/commands/PaperCommandBlockHolder.java
-@@ -0,0 +1,33 @@
+@@ -0,0 +1,34 @@
 +package io.papermc.paper.commands;
 +
 +import io.papermc.paper.adventure.PaperAdventure;
 +import io.papermc.paper.command.CommandBlockHolder;
 +import net.kyori.adventure.text.Component;
 +import net.minecraft.world.level.BaseCommandBlock;
-+import org.jetbrains.annotations.NotNull;
-+import org.jetbrains.annotations.Nullable;
++import org.jspecify.annotations.NullMarked;
++import org.jspecify.annotations.Nullable;
 +
++@NullMarked
 +public interface PaperCommandBlockHolder extends CommandBlockHolder {
 +
 +    BaseCommandBlock getCommandBlockHandle();
 +
 +    @Override
-+    default @NotNull Component lastOutput() {
-+        return PaperAdventure.asAdventure(getCommandBlockHandle().getLastOutput());
++    default Component lastOutput() {
++        return PaperAdventure.asAdventure(this.getCommandBlockHandle().getLastOutput());
 +    }
 +
 +    @Override
-+    default void lastOutput(@Nullable Component lastOutput) {
-+        getCommandBlockHandle().setLastOutput(PaperAdventure.asVanilla(lastOutput));
++    default void lastOutput(final @Nullable Component lastOutput) {
++        this.getCommandBlockHandle().setLastOutput(PaperAdventure.asVanilla(lastOutput));
 +    }
 +
 +    @Override
 +    default int getSuccessCount() {
-+        return getCommandBlockHandle().getSuccessCount();
++        return this.getCommandBlockHandle().getSuccessCount();
 +    }
 +
 +    @Override
-+    default void setSuccessCount(int successCount) {
-+        getCommandBlockHandle().setSuccessCount(successCount);
++    default void setSuccessCount(final int successCount) {
++        this.getCommandBlockHandle().setSuccessCount(successCount);
 +    }
 +}
 diff --git a/src/main/java/org/bukkit/craftbukkit/block/CraftCommandBlock.java b/src/main/java/org/bukkit/craftbukkit/block/CraftCommandBlock.java
diff --git a/patches/server/0965-Brigadier-based-command-API.patch b/patches/server/0965-Brigadier-based-command-API.patch
index d93978b6d2..997c10e4b7 100644
--- a/patches/server/0965-Brigadier-based-command-API.patch
+++ b/patches/server/0965-Brigadier-based-command-API.patch
@@ -1045,7 +1045,7 @@ index 0000000000000000000000000000000000000000..895addef908e09d527e4bc9210599e88
 +}
 diff --git a/src/main/java/io/papermc/paper/command/brigadier/argument/SignedMessageResolverImpl.java b/src/main/java/io/papermc/paper/command/brigadier/argument/SignedMessageResolverImpl.java
 new file mode 100644
-index 0000000000000000000000000000000000000000..72966584089d3fee9778f572727c9b7f4a4d4302
+index 0000000000000000000000000000000000000000..07a23be2cd7b4592108dee0ae223e71b1d00cec9
 --- /dev/null
 +++ b/src/main/java/io/papermc/paper/command/brigadier/argument/SignedMessageResolverImpl.java
 @@ -0,0 +1,30 @@
@@ -1053,13 +1053,13 @@ index 0000000000000000000000000000000000000000..72966584089d3fee9778f572727c9b7f
 +
 +import com.mojang.brigadier.context.CommandContext;
 +import com.mojang.brigadier.exceptions.CommandSyntaxException;
++import java.util.concurrent.CompletableFuture;
 +import net.kyori.adventure.chat.SignedMessage;
 +import net.minecraft.commands.CommandSourceStack;
 +import net.minecraft.commands.arguments.MessageArgument;
-+import org.jetbrains.annotations.NotNull;
-+
-+import java.util.concurrent.CompletableFuture;
++import org.jspecify.annotations.NullMarked;
 +
++@NullMarked
 +public record SignedMessageResolverImpl(MessageArgument.Message message) implements SignedMessageResolver {
 +
 +    @Override
@@ -1067,13 +1067,13 @@ index 0000000000000000000000000000000000000000..72966584089d3fee9778f572727c9b7f
 +        return this.message.text();
 +    }
 +
++    @SuppressWarnings({"rawtypes", "unchecked"})
 +    @Override
-+    public @NotNull CompletableFuture<SignedMessage> resolveSignedMessage(final String argumentName, final CommandContext erased) throws CommandSyntaxException {
-+        final CommandContext<CommandSourceStack> type = erased;
++    public CompletableFuture<SignedMessage> resolveSignedMessage(final String argumentName, final CommandContext erased) throws CommandSyntaxException {
 +        final CompletableFuture<SignedMessage> future = new CompletableFuture<>();
 +
-+        final MessageArgument.Message response = type.getArgument(argumentName, SignedMessageResolverImpl.class).message;
-+        MessageArgument.resolveChatMessage(response, type, argumentName, (message) -> {
++        final MessageArgument.Message response = ((CommandContext<CommandSourceStack>) erased).getArgument(argumentName, SignedMessageResolverImpl.class).message;
++        MessageArgument.resolveChatMessage(response, erased, argumentName, (message) -> {
 +            future.complete(message.adventureView());
 +        });
 +        return future;
diff --git a/test-plugin/src/main/java/io/papermc/testplugin/brigtests/Registration.java b/test-plugin/src/main/java/io/papermc/testplugin/brigtests/Registration.java
index f67feda8fa..035506a505 100644
--- a/test-plugin/src/main/java/io/papermc/testplugin/brigtests/Registration.java
+++ b/test-plugin/src/main/java/io/papermc/testplugin/brigtests/Registration.java
@@ -98,12 +98,12 @@ public final class Registration {
 
             commands.register(plugin.getPluginMeta(), "example", "test", Collections.emptyList(), new BasicCommand() {
                 @Override
-                public void execute(@NotNull final CommandSourceStack commandSourceStack, final @NotNull String[] args) {
+                public void execute(@NotNull final CommandSourceStack commandSourceStack, final @NotNull String @NotNull [] args) {
                     System.out.println(Arrays.toString(args));
                 }
 
                 @Override
-                public @NotNull Collection<String> suggest(final @NotNull CommandSourceStack commandSourceStack, final @NotNull String[] args) {
+                public @NotNull Collection<String> suggest(final @NotNull CommandSourceStack commandSourceStack, final @NotNull String @NotNull [] args) {
                     System.out.println(Arrays.toString(args));
                     return List.of("apple", "banana");
                 }