diff --git a/.travis.yml b/.travis.yml
index 511e187..70cd636 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,8 +3,10 @@ python:
   - 3.3
   - 3.4
 
-install: pip install -r requirements.txt
-script: flake8 --max-complexity 10 .
+install: pip install -r requirements.txt --use-mirrors
+script:
+  - flake8 --max-complexity 10 .
+  - pep257 . --explain
 
 notifications:
   email:
diff --git a/__version__.py b/__version__.py
index 70f2765..a2e1ed2 100644
--- a/__version__.py
+++ b/__version__.py
@@ -1,4 +1,3 @@
 # -*- coding: utf-8 -*-
 
-# TODO: Prerelease notation
 __version__ = (1, 2, 0)
diff --git a/requirements.txt b/requirements.txt
index 1ae3ec6..39f7088 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1 +1,2 @@
-flake8
\ No newline at end of file
+flake8
+pep257