Try that

.github/workflows/pdfs.yml

@@ -32,3 +32,15 @@ jobs:
         with:
           name: frama-c-wp-tutoriel-fr.pdf
           path: french/main.pdf
+
+  check-code:
+    name: Check code
+    runs-on: ubuntu-latest
+    container: allanblanchardgh/tutoriel_wp:frama-c
+    steps:
+      - name: Check Why3
+        run: cat /root/.why3.conf && why3 config detect
+      - name: retrieve sources
+        uses: actions/checkout@v4
+      - name: execute
+        run: cd code ; make