diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index d355da3..c6be587 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -60,12 +60,13 @@ jobs:
     - name: Unit Test
       run: |
         python -m jepler_udecimal.test
-        if ! env MICROPYPATH=. PYTHONPATH=. MICROPY_MICROPYTHON=circuitpython/ports/unix/micropython circuitpython/tests/run-tests -d examples; then
+        if ! env MICROPYPATH=. PYTHONPATH=. MICROPY_MICROPYTHON=circuitpython/ports/unix/micropython circuitpython/tests/run-tests.py -d examples; then
             for exp in *.exp; do
                 testbase=$(basename $exp .exp);
                 echo -e "\nFAILURE $testbase";
                 diff -u $testbase.exp $testbase.out;
             done
+            exit 1
         fi
     - name: Build assets
       run: circuitpython-build-bundles --package_folder_prefix jepler --filename_prefix ${{ steps.repo-name.outputs.repo-name }} --library_location .