Update to 1.21.11, Java 25, Kotlin 2.3, Gradle 9.4

Dockerfile

@@ -4,7 +4,7 @@
 # for the Dockerfile that is run on our CI/CD pipeline, see production.Dockerfile
 
 # Build the project into an executable JAR
-FROM gradle:jdk21 as build
+FROM gradle:jdk25 as build
 # Copy build files and source code
 COPY . /work
 WORKDIR /work
@@ -13,7 +13,7 @@ RUN --mount=target=/home/gradle/.gradle,type=cache \
     /usr/bin/gradle --console=plain --info --stacktrace --no-daemon -x test --build-cache build
 
 # Run the built JAR and expose port 25565
-FROM eclipse-temurin:21-jre-alpine
+FROM eclipse-temurin:25-jre-alpine
 EXPOSE 25565
 EXPOSE 50051
 WORKDIR /server

README.md

@@ -25,7 +25,7 @@ available [here](https://wiki.minestom.net).
 ## Usage
 
 Build with `./gradlew build` and run the JAR created at `build/libs/Server-x.x.x-all.jar`.
-Requires Java 21 or higher.
+Requires Java 25 or higher.
 
 ## Development
 

build-logic/src/main/kotlin/server.common-conventions.gradle.kts

@@ -7,6 +7,6 @@ plugins {
 
 tasks.withType<KotlinCompile> {
     compilerOptions {
-        jvmTarget.set(JvmTarget.JVM_21)
+        jvmTarget.set(JvmTarget.JVM_25)
     }
 }

build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     id("server.common-conventions")
-    id("com.gradleup.shadow") version "9.0.1"
-    kotlin("plugin.serialization") version "2.1.10"
+    id("com.gradleup.shadow") version "9.4.0"
+    kotlin("plugin.serialization") version "2.3.0"
     id("net.kyori.blossom") version "2.1.0"
     `maven-publish`
 }
@@ -75,7 +75,7 @@ publishing {
 
 kotlin {
     jvmToolchain {
-        languageVersion.set(JavaLanguageVersion.of(21))
+        languageVersion.set(JavaLanguageVersion.of(25))
     }
 }
 

common/build.gradle.kts

@@ -1,6 +1,6 @@
 plugins {
     id("server.common-conventions")
-    kotlin("plugin.serialization") version "2.1.10"
+    kotlin("plugin.serialization") version "2.3.0"
     `maven-publish`
 }
 
@@ -24,6 +24,7 @@ dependencies {
     implementation(libs.bundles.messaging)
     implementation(libs.serialization.json)
     implementation(libs.bundles.tinylog)
+    implementation(libs.fastutil)
 }
 
 publishing {
@@ -40,4 +41,10 @@ publishing {
 
 tasks.getByName<Test>("test") {
     useJUnitPlatform()
-}
+}
+
+kotlin {
+    jvmToolchain {
+        languageVersion.set(JavaLanguageVersion.of(25))
+    }
+}

common/src/main/kotlin/com/bluedragonmc/server/CustomPlayer.kt

@@ -10,7 +10,7 @@ import net.minestom.server.coordinate.Pos
 import net.minestom.server.entity.Entity
 import net.minestom.server.entity.GameMode
 import net.minestom.server.entity.Player
-import net.minestom.server.entity.metadata.PlayerMeta
+import net.minestom.server.entity.metadata.avatar.PlayerMeta
 import net.minestom.server.instance.Instance
 import net.minestom.server.instance.block.Block
 import net.minestom.server.network.player.GameProfile

common/src/main/kotlin/com/bluedragonmc/server/module/combat/CustomDeathMessageModule.kt

@@ -28,15 +28,15 @@ class CustomDeathMessageModule : GameModule() {
                     if (playerName != null) {
                         Component.translatable("death.attack.player", BRAND_COLOR_PRIMARY_2, player.name, playerName)
                     } else {
-                        Component.translatable("death.attack.mob", BRAND_COLOR_PRIMARY_2, player.name, Component.translatable(src.source.entityType.registry().translationKey()))
+                        Component.translatable("death.attack.mob", BRAND_COLOR_PRIMARY_2, player.name, Component.translatable(src.source!!.entityType.registry()!!.translationKey()))
                     }
                 }
                 is EntityProjectileDamage -> {
                     val playerName = (src.shooter as? Player)?.name
                     if (playerName != null) {
                         Component.translatable("death.attack.arrow", BRAND_COLOR_PRIMARY_2, player.name, playerName)
                     } else if (src.shooter != null) {
-                        Component.translatable("death.attack.arrow", BRAND_COLOR_PRIMARY_2, player.name, Component.translatable(src.shooter!!.entityType.registry().translationKey()))
+                        Component.translatable("death.attack.arrow", BRAND_COLOR_PRIMARY_2, player.name, Component.translatable(src.shooter!!.entityType.registry()!!.translationKey()))
                     } else {
                         Component.translatable("death.attack.generic", BRAND_COLOR_PRIMARY_2, player.name)
                     }

common/src/main/kotlin/com/bluedragonmc/server/module/combat/ProjectileModule.kt

@@ -346,7 +346,7 @@ class ProjectileModule : GameModule() {
             ).filter { pos ->
                 // Check if the block should be destroyed based on the radius
                 val distance = pos.distanceSquared(centerX.toDouble(), centerY.toDouble(), centerZ.toDouble())
-                val resistance = instance.getBlock(pos).registry().explosionResistance()
+                val resistance = instance.getBlock(pos).registry()!!.explosionResistance()
                 val maxStrength = strength * 1.5 - resistance / 2.0
                 if (maxStrength <= 0 || Random.nextDouble(0.0, maxStrength) < distance)
                     return@filter false
@@ -359,7 +359,7 @@ class ProjectileModule : GameModule() {
                 parent.callEvent(event)
 
                 if (dropItems && !event.isCancelled) {
-                    val material = block.registry().material()
+                    val material = block.registry()!!.material()
                     if (material != null)
                         parent.getModule<ItemDropModule>().dropItem(ItemStack.of(material), instance, pos)
                 }

common/src/main/kotlin/com/bluedragonmc/server/module/gameplay/NPCModule.kt

@@ -11,7 +11,7 @@ import net.minestom.server.MinecraftServer
 import net.minestom.server.coordinate.Pos
 import net.minestom.server.entity.*
 import net.minestom.server.entity.damage.DamageType
-import net.minestom.server.entity.metadata.PlayerMeta
+import net.minestom.server.entity.metadata.avatar.PlayerMeta
 import net.minestom.server.entity.metadata.display.AbstractDisplayMeta
 import net.minestom.server.entity.metadata.display.TextDisplayMeta
 import net.minestom.server.event.Event
@@ -144,7 +144,8 @@ class NPCModule : GameModule() {
                 GameMode.CREATIVE,
                 Component.text("[NPC] $randomName", NamedTextColor.DARK_GRAY, TextDecoration.ITALIC),
                 null,
-                0
+                0,
+                true
             )
         )
 

common/src/main/kotlin/com/bluedragonmc/server/module/vanilla/DoorsModule.kt

@@ -70,7 +70,7 @@ class DoorsModule : GameModule() {
         val shouldPlaySound = playEffect && (block.getProperty("open").equals("true")) != open
 
         if (shouldPlaySound) {
-            val (openSound, closeSound) = (getSounds(block.registry().material() ?: return) ?: return)
+            val (openSound, closeSound) = (getSounds(block.registry()!!.material() ?: return) ?: return)
             val soundEvent = if (open) openSound else closeSound
 
             val audience = mutableListOf<Player>()

common/src/main/kotlin/com/bluedragonmc/server/module/vanilla/FallDamageModule.kt

@@ -94,7 +94,7 @@ class FallDamageModule : GameModule() {
 
                         val blockPos = Pos(x.toDouble(), y.toDouble(), z.toDouble())
                         val blockCenter = blockPos.add(0.5, 0.5, 0.5)
-                        val blockBoundingBox = player.instance.getBlock(blockPos).registry().collisionShape()
+                        val blockBoundingBox = player.instance.getBlock(blockPos).registry()!!.collisionShape()
 
                         val collides = blockBoundingBox.intersectBox(player.position.sub(blockPos), expandedBoundingBox)
                         if (!collides) continue

common/src/main/kotlin/com/bluedragonmc/server/module/vanilla/ItemDropModule.kt

@@ -81,7 +81,7 @@ class ItemDropModule(var dropBlocksOnBreak: Boolean = true, var dropAllOnDeath:
         }
         eventNode.addListener(PlayerBlockBreakEvent::class.java) { event ->
             if (dropBlocksOnBreak && !event.isCancelled && !excludedBlocks.contains(event.block)) {
-                val itemStack = ItemStack.of(event.block.registry().material() ?: Material.AIR, 1)
+                val itemStack = ItemStack.of(event.block.registry()!!.material() ?: Material.AIR, 1)
                 val dropEvent = BlockItemDropEvent(event.instance, event.block, event.blockPosition, itemStack)
                 parent.callCancellable(dropEvent) {
                     dropItem(

common/src/main/kotlin/com/bluedragonmc/server/utils/BlockUtils.kt

@@ -2,7 +2,7 @@ package com.bluedragonmc.server.utils
 
 import net.minestom.server.instance.block.Block
 
-fun Block.isFullCube() = registry().collisionShape().run {
+fun Block.isFullCube() = registry()!!.collisionShape().run {
     val start = relativeStart().isZero
     val end = relativeEnd().samePoint(1.0, 1.0, 1.0)
     start && end

common/src/main/kotlin/com/bluedragonmc/server/utils/TextUtils.kt

@@ -51,29 +51,29 @@ fun Component.hoverEventTranslatable(key: String, color: TextColor): Component =
     hoverEvent(Component.translatable(key, color))
 
 fun Component.clickEvent(command: String): Component =
-    clickEvent(ClickEvent.clickEvent(ClickEvent.Action.RUN_COMMAND, command))
+    clickEvent(ClickEvent.clickEvent(ClickEvent.Action.RUN_COMMAND, ClickEvent.Payload.string(command)))
 
 fun Component.clickEvent(action: ClickEvent.Action, value: String): Component {
     if (action == ClickEvent.Action.COPY_TO_CLIPBOARD && hoverEvent() == null) {
-        return clickEvent(ClickEvent.clickEvent(action, value)).hoverEventTranslatable(
+        return clickEvent(ClickEvent.clickEvent(action, ClickEvent.Payload.string(value))).hoverEventTranslatable(
             "command.click_to_copy",
             ALT_COLOR_1
         )
     }
     if (action == ClickEvent.Action.OPEN_URL && hoverEvent() == null) {
-        return clickEvent(ClickEvent.clickEvent(action, value)).hoverEvent(
+        return clickEvent(ClickEvent.clickEvent(action, ClickEvent.Payload.string(value))).hoverEvent(
             Component.translatable(
                 "command.click_to_open_url",
                 ALT_COLOR_1,
                 Component.text(value, NamedTextColor.GRAY)
             )
         )
     }
-    return clickEvent(ClickEvent.clickEvent(action, value))
+    return clickEvent(ClickEvent.clickEvent(action, ClickEvent.Payload.string(value)))
 }
 
-fun Material.displayName() = Component.translatable(registry().translationKey())
-fun Material.displayName(color: TextColor) = Component.translatable(registry().translationKey(), color)
+fun Material.displayName() = Component.translatable(registry()!!.translationKey())
+fun Material.displayName(color: TextColor) = Component.translatable(registry()!!.translationKey(), color)
 
 fun Component.noItalic() = decoration(TextDecoration.ITALIC, false)
 fun Component.noBold() = decoration(TextDecoration.BOLD, false)

gradle/libs.versions.toml

@@ -1,8 +1,8 @@
 metadata.format.version = "1.1"
 
 [versions]
-kotlin = "2.1.10"
-minestom = "2025.07.27-1.21.8"
+kotlin = "2.3.0"
+minestom = "2026.03.03-1.21.11"
 jukebox = "a941945c86"
 configurate = "4.2.0"
 minimessage = "4.19.0"
@@ -12,14 +12,15 @@ okhttp = "4.12.0"
 serialization = "1.8.0"
 tinylog = "2.7.0"
 atlas-projectiles = "2.1.2"
+fastutil = "8.5.18"
 # Auto-generated GRPC/Protobuf messaging code
 rpc = "d40ac743b5"
 # Messaging dependencies
 grpc = "1.71.0"
 grpc-kotlin-stub = "1.4.1"
 protobuf-kotlin = "4.30.1"
 # Testing dependencies
-mockk = "1.13.11"
+mockk = "1.14.9"
 junit = "5.9.0"
 
 [libraries]
@@ -31,6 +32,7 @@ configurate = { group = "org.spongepowered", name = "configurate-yaml", version.
 configurate-extra-kotlin = { group = "org.spongepowered", name = "configurate-extra-kotlin", version.ref = "configurate" }
 minimessage = { group = "net.kyori", name = "adventure-text-minimessage", version.ref = "minimessage" }
 atlas-projectiles = { group = "ca.atlasengine", name = "atlas-projectiles", version.ref = "atlas-projectiles" }
+fastutil = { group = "it.unimi.dsi", name = "fastutil", version.ref = "fastutil" }
 kmongo = { group = "org.litote.kmongo", name = "kmongo-coroutine-serialization", version.ref = "kmongo" }
 serialization-json = { group = "org.jetbrains.kotlinx", name = "kotlinx-serialization-json", version.ref = "serialization" }
 caffeine = { group = "com.github.ben-manes.caffeine", name = "caffeine", version.ref = "caffeine" }

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.0.0-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.4.1-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

jitpack.yml

@@ -1,2 +1,2 @@
 jdk:
-  - openjdk21
+  - openjdk25

production.Dockerfile

@@ -2,15 +2,15 @@
 # This Dockerfile runs on the CI/CD pipeline when the Server is being deployed.
 
 # Build the project into an executable JAR
-FROM docker.io/library/gradle:8.13-jdk21 as build
+FROM docker.io/library/gradle:9.4-jdk25 as build
 # Copy build files and source code
 COPY . /work
 WORKDIR /work
 # Run gradle in the /work directory
 RUN /usr/bin/gradle --console=plain --info --stacktrace --no-daemon build
 
 # Run the built JAR and expose port 25565
-FROM docker.io/library/eclipse-temurin:21-jre-alpine
+FROM docker.io/library/eclipse-temurin:25-jre-alpine
 EXPOSE 25565
 EXPOSE 50051
 WORKDIR /server

settings.gradle.kts

@@ -5,4 +5,3 @@ pluginManagement {
 }
 
 include("common")
-

src/main/kotlin/com/bluedragonmc/server/Server.kt

@@ -3,13 +3,12 @@ package com.bluedragonmc.server
 import com.bluedragonmc.server.api.Environment
 import com.bluedragonmc.server.bootstrap.*
 import com.bluedragonmc.server.bootstrap.dev.DevInstanceRouter
-import com.bluedragonmc.server.bootstrap.dev.MojangAuthentication
 import com.bluedragonmc.server.bootstrap.dev.OpenToLAN
 import com.bluedragonmc.server.bootstrap.prod.AgonesIntegration
 import com.bluedragonmc.server.bootstrap.prod.InitialInstanceRouter
-import com.bluedragonmc.server.bootstrap.prod.VelocityForwarding
 import com.bluedragonmc.server.queue.GameLoader
 import com.bluedragonmc.server.queue.createEnvironment
+import net.minestom.server.Auth
 import net.minestom.server.MinecraftServer
 import org.slf4j.LoggerFactory
 import java.text.DateFormat
@@ -38,7 +37,20 @@ fun start() {
     Environment.setEnvironment(createEnvironment())
     logger.info("Starting Minecraft server in environment ${Environment.current::class.simpleName}")
 
-    val minecraftServer = MinecraftServer.init()
+    lateinit var auth: Auth
+    val velocitySecret: String? = System.getenv("PUFFIN_VELOCITY_SECRET")
+
+    if (velocitySecret != null) {
+        auth = Auth.Velocity(System.getenv("PUFFIN_VELOCITY_SECRET").trim())
+        MinecraftServer.setCompressionThreshold(0) // Disable compression because packets are being proxied
+    } else {
+        if (!Environment.isDev) {
+            logger.warn("Warning: Running in a production-like environment without Velocity forwarding!")
+        }
+        auth = Auth.Online()
+    }
+
+    val minecraftServer = MinecraftServer.init(auth)
     val eventNode = MinecraftServer.getGlobalEventHandler()
 
     val services = listOf(
@@ -55,13 +67,11 @@ fun start() {
         InitialInstanceRouter,
         IntegrationsInit,
         Jukebox,
-        MojangAuthentication,
         OpenToLAN,
         PerInstanceChat,
         PerInstanceTabList,
         ServerListPingHandler,
         TabListFormat,
-        VelocityForwarding
     ).filter { it.canHook() }
 
     // Load game plugins and preinitialize their main classes

src/main/kotlin/com/bluedragonmc/server/bootstrap/PerInstanceTabList.kt

@@ -79,6 +79,7 @@ object PerInstanceTabList : Bootstrap() {
         player.gameMode,
         player.name,
         null,
-        1024
+        1024,
+        true
     )
 }