diff --git a/.travis.yml b/.travis.yml
index dce0257..38c36b5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,8 @@
 language: python
 python:
     - 2.7
+    - 3.5
+    - 3.6
 install:
     - python bootstrap.py
     - bin/buildout
diff --git a/CHANGES.txt b/CHANGES.txt
index af407c1..d5d7fb9 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -4,7 +4,8 @@ CHANGES
 0.8.1 (unreleased)
 ------------------
 
-- Nothing changed yet.
+- Make sure to close open files
+- Official Python 3 support
 
 
 0.8.0 (2015-10-28)
diff --git a/buildout.cfg b/buildout.cfg
index a52b39e..5c86575 100644
--- a/buildout.cfg
+++ b/buildout.cfg
@@ -5,7 +5,6 @@ versions = versions
 
 [test]
 recipe = zc.recipe.testrunner
-eggs = refline.srccheck [test]
+eggs = refline.srccheck[test]
 
 [versions]
-zope.testing = 4.1.1
diff --git a/setup.py b/setup.py
index 9ba6e71..9751e11 100644
--- a/setup.py
+++ b/setup.py
@@ -33,6 +33,7 @@ def read(*rnames):
     extras_require=dict(
         test=(
             'zope.testing',
+            'zope.testrunner',
         ),
     ),
     packages=find_packages('src'),
@@ -56,9 +57,15 @@ def read(*rnames):
         'Intended Audience :: Developers',
         'License :: OSI Approved :: Zope Public License',
         'Programming Language :: Python',
+        'Programming Language :: Python :: 2',
+        'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3',
+        'Programming Language :: Python :: 3.5',
+        'Programming Language :: Python :: 3.6',
         'Natural Language :: English',
         'Operating System :: OS Independent',
         'Topic :: Internet :: WWW/HTTP',
         'Framework :: Zope3'],
     zip_safe=False,
+    entry_points={'distutils.commands': 'ftest = zope.testrunner.eggsupport:ftest'}
     )
diff --git a/src/refline/srccheck/checker.py b/src/refline/srccheck/checker.py
index 21e422b..2c64c96 100644
--- a/src/refline/srccheck/checker.py
+++ b/src/refline/srccheck/checker.py
@@ -375,7 +375,8 @@ def run(self):
 
                 if ext in self.extensions:
                     #read file once, pass the content to checkers
-                    content = open(fullname).read()
+                    with open(fullname) as f:
+                        content = f.read()
 
                     if 'checker_ignore_this_file' in content:
                         continue