diff --git a/.github/workflows/build_cmake.yml b/.github/workflows/build_cmake.yml
index 1d262865..37a451b6 100755
--- a/.github/workflows/build_cmake.yml
+++ b/.github/workflows/build_cmake.yml
@@ -77,7 +77,7 @@ jobs:
           runs-on: ubuntu-22.04
           os: linux
           debian_container: "buildpack-deps:trixie"
-          cmake_extra_config: "-DBACKEND_ONLY=ON"
+          backend_only: true
           generate_docs: true
           generate_docker: true
 
@@ -259,7 +259,7 @@ jobs:
         sudo docker exec -e DEBIAN_FRONTEND=noninteractive "debian-build" apt -y update
         sudo docker exec -e DEBIAN_FRONTEND=noninteractive "debian-build" apt -y install \
             $BRICKSTORE_QT6_DEB_PACKAGES \
-            $BRICKSTORE_GUI_QT6_DEB_PACKAGES \
+            ${{ !matrix.config.backend_only && '$BRICKSTORE_GUI_QT6_DEB_PACKAGES' || '' }} \
             debhelper lsb-release fakeroot build-essential
       shell: bash
 
@@ -298,6 +298,7 @@ jobs:
       run: |
         sudo docker exec -w /brickstore "debian-build" /usr/lib/qt6/bin/qt-cmake -G Ninja \
             -DCMAKE_BUILD_TYPE=RelWithDebInfo \
+            ${{ matrix.config.backend_only && '-DBACKEND_ONLY=ON' || '' }} \
             ${{ matrix.config.cmake_extra_config }} -B build -S .
         sudo docker exec -w /brickstore "debian-build" cmake --build build --config RelWithDebInfo \
             --parallel --target deb-package --verbose