diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index c85b86c..2c61cb7 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -10,7 +10,7 @@
 3. Activate your dev environment with `source .venv/bin/activate`
 4. Update pip packages with `pip install -U pip setuptools wheel`
 5. Install with `pip install .`
-6. Install development dependencies with `pip install tox black`
+6. Install development dependencies with `pip install tox black pytest pytest-aiohttp`
 7. Add git-hook to run test and stylecheck before commmit with
    `ln -s ../../git-hooks/pre-commit .git/hooks/pre-commit`
 8. Add git-hook to check commmit message format with