diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
new file mode 100644
index 0000000..ed2fd28
--- /dev/null
+++ b/.github/workflows/tests.yml
@@ -0,0 +1,66 @@
+name: Tests
+
+on:
+  pull_request:
+    branches: [main]
+  push:
+    branches: [main]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  test:
+    runs-on: macos-15
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Clone sibling packages
+        run: |
+          git clone https://github.com/torlando-tech/reticulum-swift.git ../reticulum-swift
+          git clone https://github.com/torlando-tech/LXMF-swift.git ../LXMF-swift
+          git clone https://github.com/torlando-tech/LXST-swift.git ../LXST-swift
+
+      - name: Select Xcode
+        run: |
+          XCODE=$(ls -d /Applications/Xcode_16*.app 2>/dev/null | sort -V | tail -1)
+          echo "Using $XCODE"
+          sudo xcode-select -s "$XCODE"
+          xcodebuild -version
+
+      - name: Find simulator
+        id: sim
+        run: |
+          DEVICE_ID=$(xcrun simctl list devices available -j \
+            | python3 -c "import sys,json; devs=json.load(sys.stdin)['devices']; print(next(d['udid'] for rt in devs for d in devs[rt] if 'iPhone' in d['name']))")
+          echo "device_id=$DEVICE_ID" >> "$GITHUB_OUTPUT"
+          echo "Using simulator: $DEVICE_ID"
+
+      - name: Build
+        run: |
+          xcodebuild build \
+            -project ColumbaApp.xcodeproj \
+            -scheme ColumbaApp \
+            -sdk iphonesimulator \
+            -destination "id=${{ steps.sim.outputs.device_id }}" \
+            CODE_SIGN_IDENTITY=- \
+            CODE_SIGNING_REQUIRED=NO \
+            CODE_SIGNING_ALLOWED=YES \
+            DEVELOPMENT_TEAM="" \
+            PROVISIONING_PROFILE_SPECIFIER=""
+
+      - name: Build and run tests
+        run: |
+          xcodebuild test \
+            -project ColumbaApp.xcodeproj \
+            -scheme ColumbaApp \
+            -sdk iphonesimulator \
+            -destination "id=${{ steps.sim.outputs.device_id }}" \
+            -only-testing:ColumbaAppTests \
+            -resultBundlePath TestResults.xcresult \
+            CODE_SIGN_IDENTITY=- \
+            CODE_SIGNING_REQUIRED=NO \
+            CODE_SIGNING_ALLOWED=YES \
+            DEVELOPMENT_TEAM="" \
+            PROVISIONING_PROFILE_SPECIFIER=""