diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 22e6d670..26c94dd3 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -81,14 +81,20 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os:
-          - ubuntu-latest
-          - macos-latest
-          - windows-latest
-    runs-on: ${{ matrix.os }}
+        env:
+          - os: ubuntu-latest
+            node: 20
+          - os: macos-latest
+            node: 20
+          - os: windows-latest
+            node: 20.12.1 # Pinned, because of https://github.com/approvals/Approvals.NodeJS/issues/176
+    runs-on: ${{ matrix.env.os }}
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v3
+        with:
+          node-version: ${{ matrix.env.node }}
+          cache: npm
       - run: npm ci
       - run: npx barnard59 run test/e2e/definitions/file-loader.ttl
       - run: npx barnard59 run test/e2e/definitions/foreach/with-handler.ttl
@@ -103,25 +109,31 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os:
-          - ubuntu-latest
-          - macos-latest
-          - windows-latest
-    runs-on: ${{ matrix.os }}
+        env:
+          - os: ubuntu-latest
+            node: 20
+          - os: macos-latest
+            node: 20
+          - os: windows-latest
+            node: 20.12.1 # Pinned, because of https://github.com/approvals/Approvals.NodeJS/issues/176
+    runs-on: ${{ matrix.env.os }}
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v3
+        with:
+          node-version: ${{ matrix.env.node }}
+          cache: npm
       - run: npm ci
       - name: pack all
         run: npm pack -ws
       - run: npm install -g barnard59-*.tgz
-        if: matrix.os == 'ubuntu-latest' || matrix.os == 'macos-latest'
+        if: matrix.env.os == 'ubuntu-latest' || matrix.env.os == 'macos-latest'
       - run: cmd /c npm install -g (Get-ChildItem -Filter barnard59-*.tgz).FullName
-        if: matrix.os == 'windows-latest'
+        if: matrix.env.os == 'windows-latest'
       - run: which barnard59
       - run: barnard59 --help
       - run: barnard59 shacl validate --shapes test/support/pipeline-shapes.ttl < test/e2e/definitions/file-loader.ttl
-        if: matrix.os == 'ubuntu-latest' || matrix.os == 'macos-latest'
+        if: matrix.env.os == 'ubuntu-latest' || matrix.os == 'macos-latest'
       - run: barnard59 shacl validate --shapes test/support/pipeline-shapes.ttl < test/e2e/definitions/file-loader.ttl
-        if: matrix.os == 'windows-latest'
+        if: matrix.env.os == 'windows-latest'
         shell: cmd