diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f05406e..11ba344 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -15,7 +15,7 @@ jobs:
         submodules: true
     - name: Setup docker
       run: |
-        brew install --cask docker && open -a Docker
+        brew install --cask docker && open /Applications/Docker.app
     - name: Setup buildx
       uses: docker/setup-buildx-action@v3
     - name: Build mediafx image
diff --git a/builders/Darwin/mediafx-build.sh b/builders/Darwin/mediafx-build.sh
index 9bd4f6a..09875df 100755
--- a/builders/Darwin/mediafx-build.sh
+++ b/builders/Darwin/mediafx-build.sh
@@ -20,10 +20,10 @@ source "$CURRENT/versions"
 
 MEDIAFX_ROOT="$(cd "$(dirname "${CURRENT}")/../"; pwd)"
 
-MEDIAFX_BUILD="${BUILD_ROOT}/build/mediafx/${BUILD_TYPE}"
+MEDIAFX_BUILD="${BUILD_ROOT:?}/build/mediafx/${BUILD_TYPE}"
 mkdir -p "$MEDIAFX_BUILD"
 
-PATH=$INSTALL_ROOT/bin:$PATH
+PATH=${INSTALL_ROOT:?}/bin:$PATH
 
 cd "$MEDIAFX_BUILD"
 (cmake -DCMAKE_BUILD_TYPE=$BUILD_TYPE --install-prefix "$INSTALL_ROOT" "$MEDIAFX_ROOT" && cmake --build . && cmake --install .) || exit 1