diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index af20391..d1b4296 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -12,7 +12,18 @@ env:
 
 jobs:
   test:
+    name: ${{ matrix.gap-branch }}
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        gap-branch:
+          - master
+          - stable-4.14
+          - stable-4.13
+          - stable-4.12
+          - stable-4.11
+          - stable-4.10
 
     steps:
       # the order of the checkout actions is important because all contents of
@@ -26,6 +37,9 @@ jobs:
         with:
           path: this-action/
       - uses: gap-actions/setup-gap@v2
+        with:
+          GAPBRANCH: ${{ matrix.gap-branch }}
+          GAP_PKGS_TO_BUILD: ''
       - uses: gap-actions/build-pkg@v1
       - uses: gap-actions/run-pkg-tests@v3
       - uses: ./this-action/
diff --git a/action.yml b/action.yml
index eb988f2..6dece31 100644
--- a/action.yml
+++ b/action.yml
@@ -4,6 +4,31 @@ description: 'Process coverage data'
 runs:
   using: "composite"
   steps:
+      - name: "Build io and profiling packages if necessary"
+        shell: bash
+        run: |
+         set -ex
+         GAPROOT=${GAPROOT-$HOME/gap}
+
+         # the following somewhat awkward `cd` invocation ensures
+         # compatibility with both GAP <= 4.11 (with package dir names like
+         # `pkg/io-1.2.3`) and GAP >= 4.12 (where it is `pkg/io`)
+         cd $GAPROOT/pkg/io || cd $GAPROOT/pkg/io-*
+         if [[ ! -f config.status ]] ; then
+           ./configure --with-gaproot=$GAPROOT
+         fi
+         make -j$(nproc)
+
+         cd $GAPROOT/pkg/profiling || cd $GAPROOT/pkg/profiling-*
+         if [[ ! -f Makefile ]] ; then
+           if [[ -f configure.ac ]] ; then
+             ./configure --with-gaproot=$GAPROOT
+           else
+             ./configure $GAPROOT
+           fi
+         fi
+         make -j$(nproc)
+
       - name: "Process coverage data"
         shell: bash
         run: |