diff --git a/build.gradle.kts b/build.gradle.kts
index 0252749c00..2a380b913a 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -21,6 +21,15 @@ subprojects {
             languageVersion = JavaLanguageVersion.of(21)
         }
     }
+
+    dependencies {
+        "testRuntimeOnly"("org.junit.platform:junit-platform-launcher")
+    }
+
+    tasks.withType<AbstractArchiveTask>().configureEach {
+        isPreserveFileTimestamps = false
+        isReproducibleFileOrder = true
+    }
 }
 
 val paperMavenPublicUrl = "https://repo.papermc.io/repository/maven-public/"
diff --git a/gradle.properties b/gradle.properties
index aeeaa7b209..7a2b3bf89e 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -8,6 +8,3 @@ updatingMinecraft=false
 org.gradle.caching=true
 org.gradle.parallel=true
 org.gradle.vfs.watch=false
-
-# TODO: this should be removed when we move things to forked JVMs
-org.gradle.jvmargs=-Xmx2G
diff --git a/paper-api-generator/build.gradle.kts b/paper-api-generator/build.gradle.kts
index e1e434773a..67d1ae285a 100644
--- a/paper-api-generator/build.gradle.kts
+++ b/paper-api-generator/build.gradle.kts
@@ -1,18 +1,18 @@
-import io.papermc.paperweight.PaperweightSourceGeneratorHelper
-import io.papermc.paperweight.extension.PaperweightSourceGeneratorExt
 import io.papermc.paperweight.util.defaultJavaLauncher
 
 plugins {
     java
+    id("io.papermc.paperweight.source-generator")
 }
 
-plugins.apply(PaperweightSourceGeneratorHelper::class)
-
-extensions.configure(PaperweightSourceGeneratorExt::class) {
-    atFile.set(projectDir.toPath().resolve("wideners.at").toFile())
+paperweight {
+    atFile.set(layout.projectDirectory.file("wideners.at"))
 }
 
 dependencies {
+    minecraftJar(project(":paper-server", "mappedJarOutgoing"))
+    implementation(project(":paper-server", "macheMinecraftLibraries"))
+
     implementation("com.squareup:javapoet:1.13.0")
     implementation(project(":paper-api"))
     implementation("io.github.classgraph:classgraph:4.8.47")
diff --git a/paper-server/build.gradle.kts b/paper-server/build.gradle.kts
index 4634193258..64c9c43dc9 100644
--- a/paper-server/build.gradle.kts
+++ b/paper-server/build.gradle.kts
@@ -11,19 +11,33 @@ val paperMavenPublicUrl = "https://repo.papermc.io/repository/maven-public/"
 
 dependencies {
     mache("io.papermc:mache:1.21.4+build.5")
+    paperclip("io.papermc:paperclip:3.0.3")
 }
 
 paperweight {
-    softSpoon = true
-    minecraftVersion = "1.21.4"
+    minecraftVersion = providers.gradleProperty("mcVersion")
     // macheOldPath = file("F:\\Projects\\PaperTooling\\mache\\versions\\1.21.4\\src\\main\\java")
     // gitFilePatches = true
 
     paper {
-        paperServerDir = file("./")
+        reobfMappingsPatch = layout.projectDirectory.file("../build-data/reobf-mappings-patch.tiny")
+        reobfPackagesToFix.addAll(
+            "co.aikar.timings",
+            "com.destroystokyo.paper",
+            "com.mojang",
+            "io.papermc.paper",
+            "ca.spottedleaf",
+            "net.kyori.adventure.bossbar",
+            "net.minecraft",
+            "org.bukkit.craftbukkit",
+            "org.spigotmc",
+        )
     }
 
-    serverProject = project(":paper-server")
+    spigot {
+        buildDataRef = "3edaf46ec1eed4115ce1b18d2846cded42577e42"
+        packageVersion = "v1_21_R3" // also needs to be updated in MappingEnvironment"
+    }
 }
 
 tasks.generateDevelopmentBundle {
diff --git a/settings.gradle.kts b/settings.gradle.kts
index 9503dfc6a6..2cc62d3e5c 100644
--- a/settings.gradle.kts
+++ b/settings.gradle.kts
@@ -3,6 +3,7 @@ import java.util.Locale
 pluginManagement {
     repositories {
         gradlePluginPortal()
+        mavenLocal()
         maven("https://repo.papermc.io/repository/maven-public/")
     }
 }