diff --git a/.github/workflows/test_and_release.yml b/.github/workflows/test_and_release.yml
index 498f89e..d6dd1f1 100644
--- a/.github/workflows/test_and_release.yml
+++ b/.github/workflows/test_and_release.yml
@@ -25,9 +25,13 @@ jobs:
 
       - run: python -m pip install hatch
       - run: hatch fmt --check
-      - run: hatch test
+      - run: hatch test --cover
       - run: hatch run types:check
 
+      - uses: codecov/codecov-action@v1
+        # We don't need to upload coverage more than once.
+        if: matrix.python-version == "3.12"
+
   release:
     name: "publish to GitHub and PyPi"
     runs-on: ubuntu-latest
@@ -36,7 +40,7 @@ jobs:
       name: release
       url: https://pypi.org/p/alpax
 
-    if: github.event_name == 'push'
+    if: github.event_name == "push"
 
     # Make sure tests pass before running.
     needs: