diff --git a/GBDaoGenerator/build.gradle b/GBDaoGenerator/build.gradle
index 8232e5718..ba4f1e38e 100644
--- a/GBDaoGenerator/build.gradle
+++ b/GBDaoGenerator/build.gradle
@@ -35,9 +35,9 @@ artifacts {
 }
 
 java {
-    sourceCompatibility = JavaVersion.VERSION_1_8
-    targetCompatibility = JavaVersion.VERSION_1_8
-    toolchain.languageVersion = JavaLanguageVersion.of(17)
+    // setting sourceCompatibility and targetCompatibility isn't required because this module
+    // ships no complied code
+    toolchain.languageVersion = JavaLanguageVersion.of(21)
 }
 
 tasks.named("distTar") {
diff --git a/app/build.gradle b/app/build.gradle
index 216ef9093..1a6308df7 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -11,6 +11,11 @@ tasks.withType(Test).configureEach {
     systemProperty "GB_LOGFILES_DIR", Files.createTempDirectory("gblog").toString()
 }
 
+// disable Java 1.8 warning
+tasks.withType(JavaCompile).configureEach {
+    options.compilerArgs << "-Xlint:-options"
+}
+
 def getVersionCode = { ->
     try {
         def commitCount = providers.exec {
@@ -68,7 +73,7 @@ def getGitHashShort = { ->
 }
 
 java {
-    toolchain.languageVersion = JavaLanguageVersion.of(17)
+    toolchain.languageVersion = JavaLanguageVersion.of(21)
 }
 
 android {
diff --git a/gradle.properties b/gradle.properties
index e4cc59368..aeb3ee89e 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -23,3 +23,6 @@ android.enableJetifier=false
 
 # FIXME: This optimizes away some classes it should not - see #3853
 android.enableR8.fullMode=false
+
+# disable Java 1.8 warning
+android.javaCompile.suppressSourceTargetDeprecationWarning=true
\ No newline at end of file