diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0055a08..1c4fad4 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -68,12 +68,12 @@ jobs:
         env:
           PYTHON: ""
       - uses: julia-actions/julia-processcoverage@v1
-      - uses: codecov/codecov-action@v3
+      - uses: codecov/codecov-action@v4
         with:
           file: ./lcov.info
           flags: unittests
           name: codecov-umbrella
-          fail_ci_if_error: false
+          fail_ci_if_error: true
           token: ${{ secrets.CODECOV_TOKEN }}
       # The standard setup of Coveralls is just annoying for parallel builds, see, e.g.,
       # https://github.com/trixi-framework/Trixi.jl/issues/691