diff --git a/.gitignore b/.gitignore
index 44f3d6b..62cc5d1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,6 +10,7 @@ __pycache__/
 # Distribution / packaging
 .Python
 env/
+venv/
 build/
 develop-eggs/
 dist/
@@ -44,6 +45,7 @@ htmlcov/
 nosetests.xml
 coverage.xml
 *,cover
+.pytest_cache/
 
 # Translations
 *.mo
diff --git a/setup.py b/setup.py
index 71feae2..6cf114f 100644
--- a/setup.py
+++ b/setup.py
@@ -7,7 +7,7 @@ with open('HISTORY.md') as history_file:
     history = history_file.read()
 
 requirements = [
-    'apistar',
+    'apistar~=0.3.9',
 ]
 
 test_requirements = [