diff --git a/.forgejo/workflows/pull_request.yml b/.forgejo/workflows/pull_request.yml
index 150669c..87ad5b7 100644
--- a/.forgejo/workflows/pull_request.yml
+++ b/.forgejo/workflows/pull_request.yml
@@ -15,7 +15,7 @@ jobs:
         uses: https://git.wbrawner.com/actions/setup-java@v4
         with:
           distribution: 'zulu'
-          java-version: '17'
+          java-version: '21'
       - name: Validate Gradle Wrapper
         uses: https://git.wbrawner.com/gradle/actions/wrapper-validation@v4
   unit_tests:
@@ -29,7 +29,7 @@ jobs:
         uses: https://git.wbrawner.com/actions/setup-java@v4
         with:
           distribution: 'zulu'
-          java-version: '17'
+          java-version: '21'
       - name: Setup Android SDK
         uses: https://git.wbrawner.com/android-actions/setup-android@v3
       - name: Setup Gradle
@@ -56,7 +56,7 @@ jobs:
 #        uses: https://git.wbrawner.com/actions/setup-java@v3
 #        with:
 #          distribution: 'zulu'
-#          java-version: '17'
+#          java-version: '21'
 #      - name: Build with Gradle
 #        uses: https://git.wbrawner.com/gradle/gradle-build-action@v2
 #        with:
diff --git a/shared/build.gradle.kts b/shared/build.gradle.kts
index be4b2c0..a82ae46 100644
--- a/shared/build.gradle.kts
+++ b/shared/build.gradle.kts
@@ -7,6 +7,7 @@ plugins {
 }
 
 kotlin {
+    jvmToolchain(21)
     androidTarget()
     listOf(iosArm64(), iosSimulatorArm64()).forEach {
         it.binaries.framework {
@@ -66,10 +67,6 @@ android {
     defaultConfig {
         minSdk = libs.versions.minSdk.get().toInt()
     }
-    compileOptions {
-        sourceCompatibility = JavaVersion.VERSION_21
-        targetCompatibility = JavaVersion.VERSION_21
-    }
     buildTypes {
         release {
             consumerProguardFiles("proguard-rules.pro")