diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index fdb9dc3..474d0c3 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -19,36 +19,32 @@ concurrency:
 jobs:
   # The CI test job
   test:
-    name: ${{ matrix.gap-branch }}
+    name: ${{ matrix.gap-version }}
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
-        gap-branch:
-          - master
-          - stable-4.15
-          - stable-4.14
-          - stable-4.13
-          - stable-4.12
-          - stable-4.11
-          - stable-4.10
-          - stable-4.9
+        gap-version:
+          - 'devel'
+          - '4.15'
+          - '4.14'
+          - '4.13'
+          - '4.12'
+          - '4.11'
+          - '4.10'
+          - '4.9'
 
     steps:
       - uses: actions/checkout@v6
-      - name: 'Install additional dependencies'
-        run: |
-          sudo apt-get update
-          sudo apt-get install singular
-      - uses: gap-actions/setup-gap@v2
+      - uses: gap-actions/setup-gap@v3
         with:
-          GAPBRANCH: ${{ matrix.gap-branch }}
-      - uses: gap-actions/build-pkg@v1
-      - uses: gap-actions/run-pkg-tests@v3
-      - uses: gap-actions/run-pkg-tests@v3
+          gap-version: ${{ matrix.gap-version }}
+      - uses: gap-actions/build-pkg@v3
+      - uses: gap-actions/run-pkg-tests@v4
+      - uses: gap-actions/run-pkg-tests@v4
         with:
-          only-needed: true
-      - uses: gap-actions/process-coverage@v2
-      - uses: codecov/codecov-action@v5
+          mode: onlyneeded
+      - uses: gap-actions/process-coverage@v3
+      - uses: codecov/codecov-action@v6
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
diff --git a/PackageInfo.g b/PackageInfo.g
index a195124..15c106d 100644
--- a/PackageInfo.g
+++ b/PackageInfo.g
@@ -88,6 +88,7 @@ Dependencies := rec(
   GAP := ">=4.8",
   NeededOtherPackages := [  ],
   SuggestedOtherPackages := [  ],
+  NeededSystemPackages := rec( Ubuntu := [["singular"]], Homebrew := [["singular"]] ),
   ExternalConditions := [ ["Requires the computer algebra system Singular",
                            "https://www.singular.uni-kl.de/"] ]
 ),