diff --git a/.github/workflows/test-core.yaml b/.github/workflows/test-core.yaml
index 6598b61..d377a15 100644
--- a/.github/workflows/test-core.yaml
+++ b/.github/workflows/test-core.yaml
@@ -19,3 +19,10 @@ jobs:
         run: cd core && python -m pip install -r requirements.txt
       - name: Test with pytest
         run: cd core && pytest --log-cli-level=INFO
+      # TODO: Only prepare code coverage data if on the master branch
+      - name: Prepare code coverage data
+        run: pytest --cov core
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v4
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
diff --git a/core/requirements.txt b/core/requirements.txt
index 6a492ba..4be8cfc 100644
--- a/core/requirements.txt
+++ b/core/requirements.txt
@@ -2,4 +2,6 @@ ortools==9.10.4067
 pandas
 ruamel.yaml
 munch
+# For CI
 pytest
+pytest-cov
diff --git a/core/tests/test_all.py b/core/tests/test_all.py
index 924aed3..ea4f6c8 100644
--- a/core/tests/test_all.py
+++ b/core/tests/test_all.py
@@ -8,12 +8,14 @@
 import pytest
 
 
+current_dir = os.path.dirname(os.path.realpath(__file__))
+
 def test_all():
-    for filepath in glob.glob("tests/testcases/*.yaml"):
-        base_filepath = os.path.splitext(filepath)[0]
+    for filepath in glob.glob(f"{current_dir}/testcases/*.yaml"):
+        base_filepath = os.path.splitext(os.path.basename(filepath))[0]
         logging.info(f"Testing '{base_filepath}' ...")
         df = nurse_scheduling.schedule(filepath, validate=False, deterministic=True)
-        with open(f"{base_filepath}.csv", 'r') as f:
+        with open(f"{current_dir}/testcases/{base_filepath}.csv", 'r') as f:
             expected_csv = f.read()
         actual_csv = df.to_csv(index=False, header=False)
         if actual_csv != expected_csv: