diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index dde8414..f1dd68f 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -1,20 +1,42 @@
-
 name: Build
 
-on: [push]
+on:
+
+  push:
+    branches: [ "main" ]
+
+  pull_request:
+    branches: [ "main" ]
 
 jobs:
+
   build:
-    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        config: [
+          { target: android, os: ubuntu-latest, tasks: testDebugUnitTest testReleaseUnitTest, continueOnError: false },
+          { target: apple, os: macos-latest, tasks: iosX64Test iosSimulatorArm64Test macosX64Test macosArm64Test tvosX64Test tvosSimulatorArm64Test watchosX64Test watchosSimulatorArm64Test, continueOnError: false },
+          { target: windows, os: windows-latest, tasks: windowsTest, continueOnError: false },
+          { target: linux, os: ubuntu-latest, tasks: linuxTest, continueOnError: false }
+        ]
+    runs-on: ${{ matrix.config.os }}
+    name: Build ${{ matrix.config.target }}
+
     steps:
       - uses: actions/checkout@v3
-      - name: Set up JDK 11 for x64
+
+      - name: Set up JDK
         uses: actions/setup-java@v3
         with:
-          java-version: '11'
-          distribution: 'adopt'
-          architecture: x64
+          java-version: '17'
+          distribution: 'temurin'
+
       - name: Build
         uses: gradle/gradle-build-action@v2
+        #continue-on-error: ${{ matrix.config.continueOnError }}
         with:
           arguments: build test
+
+      #- name: Test ${{ matrix.config.target }} targets
+      #  continue-on-error: ${{ matrix.config.continueOnError }}
+      #  run: ./gradlew ${{ matrix.config.tasks }}
diff --git a/kompack-base/build.gradle b/kompack-base/build.gradle
index fdf9942..44de373 100644
--- a/kompack-base/build.gradle
+++ b/kompack-base/build.gradle
@@ -7,7 +7,7 @@ plugins {
 
 kotlin {
     jvm {
-        jvmToolchain(8) // Java8 minimum ok?
+       // take what u get jvmToolchain(11) // Java8 minimum ok?
         withJava()
         testRuns["test"].executionTask.configure {
             useJUnitPlatform()
diff --git a/kompack-kotlin-serialization/build.gradle b/kompack-kotlin-serialization/build.gradle
index dcf07df..5e3a756 100644
--- a/kompack-kotlin-serialization/build.gradle
+++ b/kompack-kotlin-serialization/build.gradle
@@ -7,7 +7,7 @@ plugins {
 
 kotlin {
     jvm {
-        jvmToolchain(8) // Java8 minimum ok?
+        // take what you get jvmToolchain(11) // Java8 minimum ok?
         withJava()
         testRuns["test"].executionTask.configure {
             useJUnitPlatform()
diff --git a/testsuite/build.gradle b/testsuite/build.gradle
index fe32855..4d496ba 100644
--- a/testsuite/build.gradle
+++ b/testsuite/build.gradle
@@ -5,7 +5,7 @@ plugins {
 
 kotlin {
     jvm {
-        jvmToolchain(8) // Java8 minimum ok?
+      //  jvmToolchain(8) // Java8 minimum ok?
         withJava()
         testRuns["test"].executionTask.configure {
             useJUnitPlatform()