diff --git a/.gitignore b/.gitignore
index b5c5b91..7e9a9bd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,8 +4,12 @@ service-account.json
 my-test*.ics
 .vscode/
 .idea/
+.venv/
+.pytest_cache/
+.mypy_cache/
 /dist/
 /*.egg-info/
 /build/
 /.eggs/
 venv/
+mypy_report/
diff --git a/pyproject.toml b/pyproject.toml
index a44b307..bdbb6d1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,6 +34,7 @@ mypy = ">=0.960"
 types-python-dateutil = "^2.8.17"
 types-pytz = ">=2021.3.8"
 types-PyYAML = "^6.0.8"
+lxml = "^4.9.0"
 
 [tool.poetry.scripts]
 sync-ics2gcal = "sync_ics2gcal.sync_calendar:main"
@@ -51,4 +52,3 @@ module = [
     'fire'
 ]
 ignore_missing_imports = true
-