diff --git a/.travis.yml b/.travis.yml
index 6d324010..9010e77a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -10,7 +10,12 @@ python:
   - "nightly"
 # command to install dependencies
 install:
-  - pip install Flask==0.12 stem==1.5.4 pytest-cov coveralls
+  - pip install Flask==0.12 stem==1.5.4 pytest-cov coveralls flake8
+before_script:
+    # stop the build if there are Python syntax errors or undefined names
+    - flake8 . --count --select=E901,E999,F821,F822,F823 --show-source --statistics
+    # exit-zero treats all errors as warnings.  The GitHub editor is 127 chars wide
+    - flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
 # command to run tests
 script: pytest --cov=onionshare test/
 after_success: