diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index a3fbc47e3f..0bef66f90d 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -17,6 +17,6 @@ jobs:
           fetch-depth: 0
       - uses: actions/setup-java@v1
         with:
-          java-version: 17
+          java-version: 21
       - name: Build and Test
         run: bash ./gradlew clean test --stacktrace
diff --git a/README.md b/README.md
index f3b813ffe8..82c1a06265 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@ Cryptomator for Android is currently available in the following  distribution ch
 ### Dependencies
 
 * Git
-* JDK 17
+* JDK 21
 * Gradle
 
 ### Run Git and Gradle
diff --git a/build.gradle b/build.gradle
index ea6ea50216..01e3b19024 100644
--- a/build.gradle
+++ b/build.gradle
@@ -8,7 +8,7 @@ buildscript {
 	}
 	dependencies {
 		// before upgrading AGP, check https://gitlab.com/fdroid/admin/-/issues/593
-		classpath 'com.android.tools.build:gradle:8.13.2'
+		classpath 'com.android.tools.build:gradle:9.4.0'
 		classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
 		classpath "de.mannodermaus.gradle.plugins:android-junit5:1.7.1.1"
 	}
@@ -16,17 +16,13 @@ buildscript {
 
 def getVersionCode = { ->
 	try {
-		def branchName = new ByteArrayOutputStream()
-		exec {
+		def branchName = providers.exec {
 			commandLine 'git', 'rev-parse', '--abbrev-ref', 'HEAD'
-			standardOutput = branchName
-		}
-		def appBuild = new ByteArrayOutputStream()
-		exec {
-			commandLine 'git', 'rev-list', '--count', branchName.toString().trim()
-			standardOutput = appBuild
-		}
-		return Integer.parseInt(appBuild.toString().trim()) + 1958 // adding 1958 for legacy reasons
+		}.standardOutput.asText.get().trim()
+		def appBuild = providers.exec {
+			commandLine 'git', 'rev-list', '--count', branchName
+		}.standardOutput.asText.get().trim()
+		return Integer.parseInt(appBuild) + 1958 // adding 1958 for legacy reasons
 	}
 	catch (ignored) {
 		return -1
@@ -49,7 +45,7 @@ allprojects {
 }
 
 task clean(type: Delete) {
-	delete rootProject.buildDir
+	delete rootProject.layout.buildDirectory
 }
 
 def getApiKey(key) {
diff --git a/buildsystem/Dockerfile b/buildsystem/Dockerfile
index 8d82ba35f8..2c5574b735 100644
--- a/buildsystem/Dockerfile
+++ b/buildsystem/Dockerfile
@@ -20,8 +20,8 @@ RUN apt-get update -y && apt-get install -y $(cat docker/dependencies.txt)
 RUN docker/print-versions.sh docker/dependencies.txt
 
 ENV ANDROID_COMMAND_LINE_TOOLS_FILENAME commandlinetools-linux-10406996_latest.zip
-ENV ANDROID_API_LEVELS                  android-36
-ENV ANDROID_BUILD_TOOLS_VERSION         36.1.0
+ENV ANDROID_API_LEVELS                  android-37
+ENV ANDROID_BUILD_TOOLS_VERSION         37.0.0
 
 ENV ANDROID_HOME /usr/local/android-sdk-linux
 ENV PATH         ${PATH}:${ANDROID_HOME}/tools:${ANDROID_HOME}/platform-tools:${ANDROID_HOME}/cmdline-tools/bin
@@ -35,7 +35,7 @@ RUN yes | sdkmanager --update --sdk_root="${ANDROID_HOME}"
 RUN yes | sdkmanager --sdk_root="${ANDROID_HOME}" "platforms;${ANDROID_API_LEVELS}" "build-tools;${ANDROID_BUILD_TOOLS_VERSION}"
 
 RUN yes | sdkmanager --licenses --sdk_root="${ANDROID_HOME}"
-RUN update-java-alternatives -s java-1.17.0-openjdk-amd64
+RUN update-java-alternatives -s java-1.21.0-openjdk-amd64
 
 RUN rm -rf ${ANDROID_HOME}/tools
 
diff --git a/buildsystem/dependencies.gradle b/buildsystem/dependencies.gradle
index 6a1b374c6a..c06de3d62c 100644
--- a/buildsystem/dependencies.gradle
+++ b/buildsystem/dependencies.gradle
@@ -37,14 +37,13 @@ allprojects {
 }
 
 ext {
-	androidBuildToolsVersion = "36.1.0"
+	androidBuildToolsVersion = "37.0.0"
 	androidMinSdkVersion = 26
-	androidTargetSdkVersion = 36
-	androidCompileSdkVersion = 36
+	androidTargetSdkVersion = 37
+	androidCompileSdkVersion = 37
 
 	// android and java libs
 	androidVersion = '4.1.1.4'
-	multidexVersion = '2.0.1'
 	javaxAnnotationVersion = '1.0'
 
 	// support lib
@@ -109,6 +108,7 @@ ext {
 	// testing dependencies
 
 	jUnitVersion = '5.11.4'
+	jUnitPlatformVersion = '1.11.4' // keep in sync with jUnitVersion
 	assertJVersion = '1.7.1'
 	mockitoVersion = '5.23.0'
 	mockitoKotlinVersion = '6.3.0'
@@ -175,6 +175,7 @@ ext {
 			junitApi                       : "org.junit.jupiter:junit-jupiter-api:${jUnitVersion}",
 			junitEngine                    : "org.junit.jupiter:junit-jupiter-engine:${jUnitVersion}",
 			junitParams                    : "org.junit.jupiter:junit-jupiter-params:${jUnitVersion}",
+			junitPlatformLauncher          : "org.junit.platform:junit-platform-launcher:${jUnitPlatformVersion}",
 			junit4Engine                   : "org.junit.vintage:junit-vintage-engine:${jUnitVersion}",
 			minIo                          : "io.minio:minio:${minIoVersion}",
 			mockito                        : "org.mockito:mockito-core:${mockitoVersion}",
@@ -183,7 +184,6 @@ ext {
 			mockitoAndroid                 : "org.mockito:mockito-android:${mockitoAndroidVersion}",
 			msgraph                        : "com.microsoft.graph:microsoft-graph:${msgraphVersion}",
 			msgraphAuth                    : "com.microsoft.identity.client:msal:${msgraphAuthVersion}",
-			multidex                       : "androidx.multidex:multidex:${multidexVersion}",
 			okHttp                         : "com.squareup.okhttp3:okhttp:${okHttpVersion}",
 			okHttpDigest                   : "io.github.rburgst:okhttp-digest:${okHttpDigestVersion}",
 			pcloud                         : "com.github.cryptomator.pcloud-sdk-java:java-core:${pcloudVersion}",
diff --git a/buildsystem/docker/dependencies.txt b/buildsystem/docker/dependencies.txt
index a35cdad6fd..8241f297fb 100644
--- a/buildsystem/docker/dependencies.txt
+++ b/buildsystem/docker/dependencies.txt
@@ -2,4 +2,4 @@ apt-utils=2.9.3
 wget=1.24.5-1
 git=1:2.45.1-1
 unzip=6.0-28
-openjdk-17-jdk=17.0.11+9-1
+openjdk-21-jdk=21.0.3+9-2
diff --git a/data/build.gradle b/data/build.gradle
index a3da15e213..037ea0331c 100644
--- a/data/build.gradle
+++ b/data/build.gradle
@@ -25,13 +25,13 @@ android {
 	}
 
 	compileOptions {
-		sourceCompatibility JavaVersion.VERSION_17
-		targetCompatibility JavaVersion.VERSION_17
+		sourceCompatibility JavaVersion.VERSION_21
+		targetCompatibility JavaVersion.VERSION_21
 
 		coreLibraryDesugaringEnabled true
 	}
 
-	kotlinOptions { jvmTarget = JavaVersion.VERSION_17 }
+	kotlinOptions { jvmTarget = JavaVersion.VERSION_21 }
 	buildFeatures {
 		buildConfig true
 	}
@@ -213,6 +213,7 @@ dependencies {
 	testRuntimeOnly dependencies.junitEngine
 	testImplementation dependencies.junitParams
 	testRuntimeOnly dependencies.junit4Engine
+	testRuntimeOnly dependencies.junitPlatformLauncher
 	implementation dependencies.androidxTestJunitKtln
 
 	testImplementation dependencies.mockito
diff --git a/domain/build.gradle b/domain/build.gradle
index 923d813be7..8f1a6fd890 100644
--- a/domain/build.gradle
+++ b/domain/build.gradle
@@ -19,12 +19,12 @@ android {
 	}
 
 	compileOptions {
-		sourceCompatibility JavaVersion.VERSION_17
-		targetCompatibility JavaVersion.VERSION_17
+		sourceCompatibility JavaVersion.VERSION_21
+		targetCompatibility JavaVersion.VERSION_21
 
 		coreLibraryDesugaringEnabled true
 	}
-	kotlinOptions { jvmTarget = JavaVersion.VERSION_17 }
+	kotlinOptions { jvmTarget = JavaVersion.VERSION_21 }
 	buildFeatures {
 		buildConfig true
 	}
@@ -96,6 +96,7 @@ dependencies {
 	testImplementation dependencies.junitParams
 
 	testRuntimeOnly dependencies.junit4Engine
+	testRuntimeOnly dependencies.junitPlatformLauncher
 
 	testImplementation dependencies.mockito
 	testImplementation dependencies.mockitoKotlin
diff --git a/generator-api/build.gradle b/generator-api/build.gradle
index 45cabb4c40..72a3249dbc 100644
--- a/generator-api/build.gradle
+++ b/generator-api/build.gradle
@@ -1,14 +1,16 @@
 apply plugin: 'java'
 
-//noinspection GroovyUnusedAssignment
-sourceCompatibility = 17
-//noinspection GroovyUnusedAssignment
-targetCompatibility = 17
+java {
+	sourceCompatibility = JavaVersion.VERSION_21
+	targetCompatibility = JavaVersion.VERSION_21
+}
 
 dependencies {
 	def dependencies = rootProject.ext.dependencies
 
-	implementation(dependencies.android) {
+	// compile-only: only @Intent references android.app.Activity, and AGP 9 no longer
+	// auto-ignores this legacy jar, so its transitives would clash on the app runtime classpath
+	compileOnly(dependencies.android) {
 		exclude module: 'httpclient'
 	}
 }
diff --git a/generator/build.gradle b/generator/build.gradle
index 9fffdf15e6..2e63052afb 100644
--- a/generator/build.gradle
+++ b/generator/build.gradle
@@ -1,9 +1,9 @@
 apply plugin: 'java'
 
-//noinspection GroovyUnusedAssignment
-sourceCompatibility = 17
-//noinspection GroovyUnusedAssignment
-targetCompatibility = 17
+java {
+	sourceCompatibility = JavaVersion.VERSION_21
+	targetCompatibility = JavaVersion.VERSION_21
+}
 
 repositories {
 	mavenCentral()
diff --git a/generator/src/main/java/org/cryptomator/generator/ActivityProcessor.java b/generator/src/main/java/org/cryptomator/generator/ActivityProcessor.java
index 7c99c56b67..08cb9a3b88 100644
--- a/generator/src/main/java/org/cryptomator/generator/ActivityProcessor.java
+++ b/generator/src/main/java/org/cryptomator/generator/ActivityProcessor.java
@@ -18,7 +18,7 @@
 import javax.tools.JavaFileObject;
 
 @SupportedAnnotationTypes("org.cryptomator.generator.Activity")
-@SupportedSourceVersion(SourceVersion.RELEASE_17)
+@SupportedSourceVersion(SourceVersion.RELEASE_21)
 public class ActivityProcessor extends BaseProcessor {
 
 	@Override
diff --git a/generator/src/main/java/org/cryptomator/generator/CallbackProcessor.java b/generator/src/main/java/org/cryptomator/generator/CallbackProcessor.java
index 09b692a48b..a6c937998f 100644
--- a/generator/src/main/java/org/cryptomator/generator/CallbackProcessor.java
+++ b/generator/src/main/java/org/cryptomator/generator/CallbackProcessor.java
@@ -22,7 +22,7 @@
 import javax.tools.JavaFileObject;
 
 @SupportedAnnotationTypes("org.cryptomator.generator.Callback")
-@SupportedSourceVersion(SourceVersion.RELEASE_17)
+@SupportedSourceVersion(SourceVersion.RELEASE_21)
 public class CallbackProcessor extends BaseProcessor {
 
 	@Override
diff --git a/generator/src/main/java/org/cryptomator/generator/FragmentProcessor.java b/generator/src/main/java/org/cryptomator/generator/FragmentProcessor.java
index 8ab84be615..93b5e5db6b 100644
--- a/generator/src/main/java/org/cryptomator/generator/FragmentProcessor.java
+++ b/generator/src/main/java/org/cryptomator/generator/FragmentProcessor.java
@@ -18,7 +18,7 @@
 import javax.tools.JavaFileObject;
 
 @SupportedAnnotationTypes("org.cryptomator.generator.Fragment")
-@SupportedSourceVersion(SourceVersion.RELEASE_17)
+@SupportedSourceVersion(SourceVersion.RELEASE_21)
 public class FragmentProcessor extends BaseProcessor {
 
 	@Override
diff --git a/generator/src/main/java/org/cryptomator/generator/InstanceStateProcessor.java b/generator/src/main/java/org/cryptomator/generator/InstanceStateProcessor.java
index 86b55b4464..109609e35d 100644
--- a/generator/src/main/java/org/cryptomator/generator/InstanceStateProcessor.java
+++ b/generator/src/main/java/org/cryptomator/generator/InstanceStateProcessor.java
@@ -19,7 +19,7 @@
 import javax.tools.JavaFileObject;
 
 @SupportedAnnotationTypes("org.cryptomator.generator.InstanceState")
-@SupportedSourceVersion(SourceVersion.RELEASE_17)
+@SupportedSourceVersion(SourceVersion.RELEASE_21)
 public class InstanceStateProcessor extends BaseProcessor {
 
 	@Override
diff --git a/generator/src/main/java/org/cryptomator/generator/IntentProcessor.java b/generator/src/main/java/org/cryptomator/generator/IntentProcessor.java
index 28d31a2907..d34c0c684d 100644
--- a/generator/src/main/java/org/cryptomator/generator/IntentProcessor.java
+++ b/generator/src/main/java/org/cryptomator/generator/IntentProcessor.java
@@ -22,7 +22,7 @@
 import javax.tools.JavaFileObject;
 
 @SupportedAnnotationTypes("org.cryptomator.generator.Intent")
-@SupportedSourceVersion(SourceVersion.RELEASE_17)
+@SupportedSourceVersion(SourceVersion.RELEASE_21)
 public class IntentProcessor extends BaseProcessor {
 
 	@Override
diff --git a/generator/src/main/java/org/cryptomator/generator/UseCaseProcessor.java b/generator/src/main/java/org/cryptomator/generator/UseCaseProcessor.java
index 9d2321fbd3..7fbd32cbe9 100644
--- a/generator/src/main/java/org/cryptomator/generator/UseCaseProcessor.java
+++ b/generator/src/main/java/org/cryptomator/generator/UseCaseProcessor.java
@@ -15,7 +15,7 @@
 import javax.tools.JavaFileObject;
 
 @SupportedAnnotationTypes("org.cryptomator.generator.UseCase")
-@SupportedSourceVersion(SourceVersion.RELEASE_17)
+@SupportedSourceVersion(SourceVersion.RELEASE_21)
 public class UseCaseProcessor extends BaseProcessor {
 
 	@Override
diff --git a/gradle.properties b/gradle.properties
index 5db8c731d8..b4f0a9ec90 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -3,6 +3,13 @@ android.useAndroidX=true
 android.enableJetifier=true
 android.jetifier.ignorelist=jackson-core,fastdoubleparser
 kapt.incremental.apt=false
-android.defaults.buildfeatures.buildconfig=true
 android.nonTransitiveRClass=false
 android.nonFinalResIds=false
+# AGP 9 provides Kotlin support itself and disables the legacy variant API; both are
+# still needed while this project applies the standalone 'kotlin-android' plugin,
+# which calls applicationVariants/libraryVariants. see https://kotl.in/gradle/agp-built-in-kotlin
+android.builtInKotlin=false
+android.newDsl=false
+# the generator annotations take R.layout constants (e.g. @BottomSheet(R.layout.x)), which
+# the app compile-time R class does not provide: 'element value must be a constant expression'
+android.enableAppCompileTimeRClass=false
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
index 1b33c55baa..b1b8ef56b4 100644
Binary files a/gradle/wrapper/gradle-wrapper.jar and b/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index aaaabb3cb9..65d8749eab 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,7 +1,10 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.14.4-bin.zip
+distributionSha256Sum=bbaeb2fef8710818cf0e261201dab964c572f92b942812df0c3620d62a529a01
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.6.0-bin.zip
 networkTimeout=10000
+retries=0
+retryBackOffMs=500
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
diff --git a/gradlew b/gradlew
index 23d15a9367..249efbb032 100755
--- a/gradlew
+++ b/gradlew
@@ -1,7 +1,7 @@
 #!/bin/sh
 
 #
-# Copyright © 2015-2021 the original authors.
+# Copyright © 2015 the original authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -20,7 +20,7 @@
 
 ##############################################################################
 #
-#   Gradle start up script for POSIX generated by Gradle.
+#   gradlew start up script for POSIX generated by Gradle.
 #
 #   Important for running:
 #
@@ -29,7 +29,7 @@
 #       bash, then to run this script, type that shell name before the whole
 #       command line, like:
 #
-#           ksh Gradle
+#           ksh gradlew
 #
 #       Busybox and similar reduced shells will NOT work, because this script
 #       requires all of these POSIX shell features:
@@ -57,7 +57,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/3d91ce3b8caaf77ad09f381f43615b715b53f72c/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.
@@ -114,7 +114,6 @@ case "$( uname )" in                #(
   NONSTOP* )        nonstop=true ;;
 esac
 
-CLASSPATH="\\\"\\\""
 
 
 # Determine the Java command to use to start the JVM.
@@ -172,7 +171,6 @@ fi
 # For Cygwin or MSYS, switch paths to Windows format before running java
 if "$cygwin" || "$msys" ; then
     APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
-    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
 
     JAVACMD=$( cygpath --unix "$JAVACMD" )
 
@@ -212,7 +210,6 @@ DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
-        -classpath "$CLASSPATH" \
         -jar "$APP_HOME/gradle/wrapper/gradle-wrapper.jar" \
         "$@"
 
diff --git a/gradlew.bat b/gradlew.bat
index 5eed7ee845..8508ef684d 100644
--- a/gradlew.bat
+++ b/gradlew.bat
@@ -19,12 +19,12 @@
 @if "%DEBUG%"=="" @echo off
 @rem ##########################################################################
 @rem
-@rem  Gradle startup script for Windows
+@rem  gradlew startup script for Windows
 @rem
 @rem ##########################################################################
 
-@rem Set local scope for the variables with windows NT shell
-if "%OS%"=="Windows_NT" setlocal
+@rem Set local scope for the variables, and ensure extensions are enabled
+setlocal EnableExtensions
 
 set DIRNAME=%~dp0
 if "%DIRNAME%"=="" set DIRNAME=.
@@ -51,7 +51,7 @@ echo. 1>&2
 echo Please set the JAVA_HOME variable in your environment to match the 1>&2
 echo location of your Java installation. 1>&2
 
-goto fail
+"%COMSPEC%" /c exit 1
 
 :findJavaFromJavaHome
 set JAVA_HOME=%JAVA_HOME:"=%
@@ -65,30 +65,18 @@ echo. 1>&2
 echo Please set the JAVA_HOME variable in your environment to match the 1>&2
 echo location of your Java installation. 1>&2
 
-goto fail
+"%COMSPEC%" /c exit 1
 
 :execute
 @rem Setup the command line
 
-set CLASSPATH=
 
 
-@rem Execute Gradle
-"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %*
+@rem Execute gradlew
+@rem endlocal doesn't take effect until after the line is parsed and variables are expanded
+@rem which allows us to clear the local environment before executing the java command
+endlocal & "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %* & call :exitWithErrorLevel
 
-:end
-@rem End local scope for the variables with windows NT shell
-if %ERRORLEVEL% equ 0 goto mainEnd
-
-:fail
-rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
-rem the _cmd.exe /c_ return code!
-set EXIT_CODE=%ERRORLEVEL%
-if %EXIT_CODE% equ 0 set EXIT_CODE=1
-if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
-exit /b %EXIT_CODE%
-
-:mainEnd
-if "%OS%"=="Windows_NT" endlocal
-
-:omega
+:exitWithErrorLevel
+@rem Use "%COMSPEC%" /c exit to allow operators to work properly in scripts
+"%COMSPEC%" /c exit %ERRORLEVEL%
diff --git a/presentation/build.gradle b/presentation/build.gradle
index 62bf1ae20f..8ac3d7f3c4 100644
--- a/presentation/build.gradle
+++ b/presentation/build.gradle
@@ -33,21 +33,21 @@ android {
 		versionCode globalConfiguration["androidVersionCode"]
 		versionName globalConfiguration["androidVersionName"]
 
-		multiDexEnabled true
 		testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'
 	}
 
 	compileOptions {
-		sourceCompatibility JavaVersion.VERSION_17
-		targetCompatibility JavaVersion.VERSION_17
+		sourceCompatibility JavaVersion.VERSION_21
+		targetCompatibility JavaVersion.VERSION_21
 
 		coreLibraryDesugaringEnabled true
 	}
 
-	kotlinOptions { jvmTarget = JavaVersion.VERSION_17 }
+	kotlinOptions { jvmTarget = JavaVersion.VERSION_21 }
 	buildFeatures {
 		viewBinding true
 		buildConfig true
+		resValues true
 	}
 
 	defaultConfig.manifestPlaceholders = [
@@ -242,9 +242,6 @@ dependencies {
 
 	playstoreiapImplementation dependencies.billing
 
-	// multidex
-	implementation dependencies.multidex
-
 	implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
 
 	// test
@@ -284,6 +281,7 @@ dependencies {
 	testRuntimeOnly dependencies.junitEngine
 	testImplementation dependencies.junitParams
 	testRuntimeOnly dependencies.junit4Engine
+	testRuntimeOnly dependencies.junitPlatformLauncher
 
 	testImplementation dependencies.mockito
 	testImplementation dependencies.mockitoKotlin
diff --git a/presentation/src/main/java/org/cryptomator/presentation/CryptomatorApp.kt b/presentation/src/main/java/org/cryptomator/presentation/CryptomatorApp.kt
index 40f1a9f1da..c412cbd237 100644
--- a/presentation/src/main/java/org/cryptomator/presentation/CryptomatorApp.kt
+++ b/presentation/src/main/java/org/cryptomator/presentation/CryptomatorApp.kt
@@ -1,6 +1,7 @@
 package org.cryptomator.presentation
 
 import android.app.Activity
+import android.app.Application
 import android.content.ComponentName
 import android.content.Context
 import android.content.Intent
@@ -9,7 +10,6 @@ import android.os.Build
 import android.os.IBinder
 import android.os.StrictMode
 import androidx.appcompat.app.AppCompatDelegate
-import androidx.multidex.MultiDexApplication
 import org.cryptomator.data.cloud.crypto.Cryptors
 import org.cryptomator.data.cloud.crypto.CryptorsModule
 import org.cryptomator.data.repository.RepositoryModule
@@ -38,7 +38,7 @@ import java.util.concurrent.atomic.AtomicInteger
 import io.reactivex.plugins.RxJavaPlugins
 import timber.log.Timber
 
-class CryptomatorApp : MultiDexApplication(), HasComponent<ApplicationComponent> {
+class CryptomatorApp : Application(), HasComponent<ApplicationComponent> {
 
 	private val appCryptors = Cryptors.Delegating()
 	private lateinit var applicationComponent: ApplicationComponent
diff --git a/settings.gradle b/settings.gradle
index 326464e57f..821dcc67d3 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -1 +1,6 @@
+// pins the Kotlin module name, which is used to mangle internal members, so it no longer depends on the
+// name of the checkout directory; 'project' matches the Docker mount path in buildsystem/Dockerfile, so
+// APKs already published from there stay reproducible. see https://github.com/cryptomator/android/issues/645
+rootProject.name = 'project'
+
 include ':generator', ':presentation', ':generator-api', ':domain', ':data', ':util'
diff --git a/util/build.gradle b/util/build.gradle
index b6102adfe2..278aab13f0 100644
--- a/util/build.gradle
+++ b/util/build.gradle
@@ -19,10 +19,10 @@ android {
 	}
 
 	compileOptions {
-		sourceCompatibility JavaVersion.VERSION_17
-		targetCompatibility JavaVersion.VERSION_17
+		sourceCompatibility JavaVersion.VERSION_21
+		targetCompatibility JavaVersion.VERSION_21
 	}
-	kotlinOptions { jvmTarget = JavaVersion.VERSION_17 }
+	kotlinOptions { jvmTarget = JavaVersion.VERSION_21 }
 	buildFeatures {
 		buildConfig true
 	}
@@ -104,6 +104,7 @@ dependencies {
 	testRuntimeOnly dependencies.junitEngine
 	testImplementation dependencies.junitParams
 	testRuntimeOnly dependencies.junit4Engine
+	testRuntimeOnly dependencies.junitPlatformLauncher
 
 	testImplementation dependencies.hamcrest
 	testImplementation dependencies.mockito