diff --git a/.travis.yml b/.travis.yml
index 4d69048..8837171 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,4 +12,5 @@ install:
     - pip install -U . -r requirements-test.txt
 
 script:
+    - mypy tractor/  --ignore-missing-imports
     - pytest tests/ --no-print-logs
diff --git a/requirements-test.txt b/requirements-test.txt
index 285c77f..447b18c 100644
--- a/requirements-test.txt
+++ b/requirements-test.txt
@@ -1,3 +1,4 @@
 pytest
 pytest-trio
 pdbpp
+mypy