diff --git a/pyproject.toml b/pyproject.toml
index ac8942b..802851e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -35,3 +35,9 @@ column_limit = 200
 [tool.pylint]
 max-line-length = 200
 ignore-paths = ["parity_tensor/_version.py"]
+
+[tool.mypy]
+disallow_untyped_calls = true
+disallow_untyped_defs = true
+disallow_incomplete_defs = true
+check_untyped_defs = true