diff --git a/.travis.yml b/.travis.yml
index 7976b104e..65be1d0e0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -24,8 +24,13 @@ before_install:
 
 install:
   - echo "No install action required. Implicitly performed by the testing."
+  - pip install flake8
 
-# before_script:
+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
+  # 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
 
 script:
   - python setup.py test --pytest-args "tests/ --doctest-modules -v --cov moviepy --cov-report term-missing"