diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index da6d70e..ec7af40 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -23,7 +23,7 @@ jobs:
         shell: bash
         run: |
           apt -y update
-          apt install -y python3-venv
+          apt install -y python3-venv curl
           python -m venv venv
           source venv/bin/activate
 
@@ -38,4 +38,10 @@ jobs:
 
       - name: Test
         shell: bash
-        run: pytest -rs tests
+        run: pytest --cov=openmc_mcnp_adapter --cov-branch --cov-report=xml -rs tests
+
+      - name: Upload coverage reports to Codecov
+        uses: codecov/codecov-action@v5
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          slug: openmc-dev/openmc_mcnp_adapter
diff --git a/pyproject.toml b/pyproject.toml
index 017efb2..dd5a130 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -33,7 +33,7 @@ classifiers = [
 ]
 
 [project.optional-dependencies]
-test = ["pytest"]
+test = ["pytest", "pytest-cov"]
 
 [project.urls]
 "Bug Tracker" = "https://github.com/openmc-dev/openmc_mcnp_adapter/issues"
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..e69de29