diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7f81a700..1d54d49d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -129,11 +129,26 @@ jobs:
         cmake -E rename build/$BUILD_TYPE/libpng16_static.lib libpng.lib
         cmake -E rename build/pnglibconf.h pnglibconf.h
 
+    - name: Install GS1 Syntax Engine
+      shell: bash
+      run: |
+        git clone --depth=1 https://github.com/gitlost/gs1-syntax-engine && cd gs1-syntax-engine/src/c-lib
+        cmake -B build -A Win32 -DCMAKE_BUILD_TYPE=$BUILD_TYPE
+        cmake --build build --config $BUILD_TYPE
+        cmake -E rename build/$BUILD_TYPE/gs1encoders.lib gs1encoders.lib
+
+    - name: Install Qt5
+      uses: jurplel/install-qt-action@v4
+      with:
+        version: 5.15.2
+        arch: win32_msvc2019
+        dir: .
+
     - name: Configure CMake
       working-directory: build
       shell: bash
       run: |
-        cmake $GITHUB_WORKSPACE -A Win32 -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DZINT_TEST=ON -DZINT_STATIC=ON -DZINT_USE_QT=OFF -DZLIB_ROOT="${GITHUB_WORKSPACE}/zlib" -DPNG_ROOT="${GITHUB_WORKSPACE}/lpng"
+        cmake $GITHUB_WORKSPACE -A Win32 -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DZINT_TEST=ON -DZINT_STATIC=ON -DZLIB_ROOT="${GITHUB_WORKSPACE}/zlib" -DPNG_ROOT="${GITHUB_WORKSPACE}/lpng" -DGS1SE_PATH="${GITHUB_WORKSPACE}/gs1-syntax-engine/src/c-lib"
 
     - name: Build
       working-directory: build
@@ -143,7 +158,7 @@ jobs:
     - name: Test
       working-directory: build
       shell: bash
-      run: PATH=$PATH:"$(pwd)/backend/$BUILD_TYPE:$(pwd)/frontend/$BUILD_TYPE" ctest -V -C $BUILD_TYPE
+      run: PATH=$PATH:"$(pwd)/backend/$BUILD_TYPE:$(pwd)/frontend/$BUILD_TYPE" QT_QPA_PLATFORM=offscreen ctest -V -C $BUILD_TYPE
 
   build-windows-64bit:
     runs-on: windows-latest
@@ -173,10 +188,24 @@ jobs:
         cmake -E rename build/$BUILD_TYPE/libpng16_static.lib libpng.lib
         cmake -E rename build/pnglibconf.h pnglibconf.h
 
+    - name: Install GS1 Syntax Engine
+      shell: bash
+      run: |
+        git clone --depth=1 https://github.com/gitlost/gs1-syntax-engine && cd gs1-syntax-engine/src/c-lib
+        cmake -B build -DCMAKE_BUILD_TYPE=$BUILD_TYPE
+        cmake --build build --config $BUILD_TYPE
+        cmake -E rename build/$BUILD_TYPE/gs1encoders.lib gs1encoders.lib
+
+    - name: Install Qt6
+      uses: jurplel/install-qt-action@v4
+      with:
+        version: 6.9.2
+        dir: .
+
     - name: Configure CMake
       working-directory: build
       shell: bash
-      run: cmake $GITHUB_WORKSPACE -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DZINT_TEST=ON -DZINT_STATIC=ON -DZINT_USE_QT=OFF -DZLIB_ROOT="${GITHUB_WORKSPACE}/zlib" -DPNG_ROOT="${GITHUB_WORKSPACE}/lpng"
+      run: cmake $GITHUB_WORKSPACE -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DZINT_TEST=ON -DZINT_STATIC=ON -DZINT_QT6=ON -DZLIB_ROOT="${GITHUB_WORKSPACE}/zlib" -DPNG_ROOT="${GITHUB_WORKSPACE}/lpng" -DGS1SE_PATH="${GITHUB_WORKSPACE}/gs1-syntax-engine/src/c-lib"
 
     - name: Build
       working-directory: build
@@ -186,7 +215,7 @@ jobs:
     - name: Test
       working-directory: build
       shell: bash
-      run: PATH=$PATH:"$(pwd)/backend/$BUILD_TYPE:$(pwd)/frontend/$BUILD_TYPE" ctest -V -C $BUILD_TYPE
+      run: PATH=$PATH:"$(pwd)/backend/$BUILD_TYPE:$(pwd)/frontend/$BUILD_TYPE" QT_QPA_PLATFORM=offscreen ctest -V -C $BUILD_TYPE
 
   build-macOS:
     runs-on: macOS-latest