diff --git a/.travis.yml b/.travis.yml
index ce48ab219..d0e5e62d1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -20,9 +20,9 @@ matrix:
       os: osx
       osx_image: xcode7.1
     - python: 3.5
-      env: SCOPE="netlib"
+      env: SCOPE="netlib ./test/mitmproxy/script"
     - python: 3.5
-      env: SCOPE="netlib" NO_ALPN=1
+      env: SCOPE="netlib ./test/mitmproxy/script" NO_ALPN=1
     - python: 2.7
       env: DOCS=1
       script: 'cd docs && make html'
diff --git a/mitmproxy/contentviews.py b/mitmproxy/contentviews.py
index 5335b59c5..1b0f389fb 100644
--- a/mitmproxy/contentviews.py
+++ b/mitmproxy/contentviews.py
@@ -13,7 +13,7 @@ requests, the query parameters are passed as the ``query`` keyword argument.
 
 """
 from __future__ import (absolute_import, print_function, division)
-import cStringIO
+from six.moves import cStringIO as StringIO
 import json
 import logging
 import subprocess
@@ -397,7 +397,7 @@ class ViewImage(View):
 
     def __call__(self, data, **metadata):
         try:
-            img = Image.open(cStringIO.StringIO(data))
+            img = Image.open(StringIO(data))
         except IOError:
             return None
         parts = [
diff --git a/mitmproxy/contrib/wbxml/ASCommandResponse.py b/mitmproxy/contrib/wbxml/ASCommandResponse.py
index 08d034456..f5f62e856 100644
--- a/mitmproxy/contrib/wbxml/ASCommandResponse.py
+++ b/mitmproxy/contrib/wbxml/ASCommandResponse.py
@@ -27,7 +27,7 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 '''
-from ASWBXML import ASWBXML
+from .ASWBXML import ASWBXML
 import logging
 
 class ASCommandResponse:
diff --git a/mitmproxy/contrib/wbxml/ASWBXML.py b/mitmproxy/contrib/wbxml/ASWBXML.py
index 926d18c03..009ba48f0 100644
--- a/mitmproxy/contrib/wbxml/ASWBXML.py
+++ b/mitmproxy/contrib/wbxml/ASWBXML.py
@@ -30,10 +30,10 @@ THE SOFTWARE.
 import xml.dom.minidom
 import logging
 
-from ASWBXMLCodePage import ASWBXMLCodePage
-from ASWBXMLByteQueue import ASWBXMLByteQueue
-from GlobalTokens import GlobalTokens
-from InvalidDataException import InvalidDataException
+from .ASWBXMLCodePage import ASWBXMLCodePage
+from .ASWBXMLByteQueue import ASWBXMLByteQueue
+from .GlobalTokens import GlobalTokens
+from .InvalidDataException import InvalidDataException
 
 class ASWBXML:
 	versionByte = 0x03
diff --git a/mitmproxy/contrib/wbxml/ASWBXMLByteQueue.py b/mitmproxy/contrib/wbxml/ASWBXMLByteQueue.py
index c7a9e0a55..ecc76efb5 100644
--- a/mitmproxy/contrib/wbxml/ASWBXMLByteQueue.py
+++ b/mitmproxy/contrib/wbxml/ASWBXMLByteQueue.py
@@ -27,7 +27,7 @@ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 '''
-from Queue import Queue
+from six.moves.queue import Queue
 import logging
 
 class ASWBXMLByteQueue(Queue):
diff --git a/mitmproxy/controller.py b/mitmproxy/controller.py
index 9a059856e..fedfce628 100644
--- a/mitmproxy/controller.py
+++ b/mitmproxy/controller.py
@@ -1,5 +1,5 @@
 from __future__ import absolute_import
-import Queue
+from six.moves import queue
 import threading
 
 
@@ -27,7 +27,7 @@ class Reply:
 
     def __init__(self, obj):
         self.obj = obj
-        self.q = Queue.Queue()
+        self.q = queue.Queue()
         self.acked = False
 
     def __call__(self, msg=None):
@@ -56,7 +56,7 @@ class Channel:
             try:
                 # The timeout is here so we can handle a should_exit event.
                 g = m.reply.q.get(timeout=0.5)
-            except Queue.Empty:  # pragma: no cover
+            except queue.Empty:  # pragma: no cover
                 continue
             return g
 
@@ -98,7 +98,7 @@ class Master(object):
             server may be None if no server is needed.
         """
         self.server = server
-        self.masterq = Queue.Queue()
+        self.masterq = queue.Queue()
         self.should_exit = threading.Event()
 
     def tick(self, q, timeout):
@@ -113,7 +113,7 @@ class Master(object):
                 self.handle(*msg)
                 q.task_done()
                 changed = True
-        except Queue.Empty:
+        except queue.Empty:
             pass
         return changed
 
diff --git a/mitmproxy/models/http.py b/mitmproxy/models/http.py
index 0338945b1..21096a39e 100644
--- a/mitmproxy/models/http.py
+++ b/mitmproxy/models/http.py
@@ -1,5 +1,5 @@
 from __future__ import (absolute_import, print_function, division)
-import Cookie
+from six.moves import http_cookies as Cookie
 import copy
 import warnings
 from email.utils import parsedate_tz, formatdate, mktime_tz
diff --git a/mitmproxy/script/concurrent.py b/mitmproxy/script/concurrent.py
index f0f5e3cd5..57ee37dec 100644
--- a/mitmproxy/script/concurrent.py
+++ b/mitmproxy/script/concurrent.py
@@ -47,7 +47,7 @@ class ScriptThread(threading.Thread):
 
 
 def concurrent(fn):
-    if fn.func_name in (
+    if fn.__name__ in (
             "request",
             "response",
             "error",
@@ -60,4 +60,4 @@ def concurrent(fn):
 
         return _concurrent
     raise NotImplementedError(
-        "Concurrent decorator not supported for '%s' method." % fn.func_name)
+        "Concurrent decorator not supported for '%s' method." % fn.__name__)
diff --git a/mitmproxy/script/script.py b/mitmproxy/script/script.py
index edc17d43a..f142daca1 100644
--- a/mitmproxy/script/script.py
+++ b/mitmproxy/script/script.py
@@ -8,6 +8,9 @@ import os
 import shlex
 import traceback
 import sys
+
+import six
+
 from ..exceptions import ScriptException
 
 
@@ -40,7 +43,8 @@ class Script(object):
     def parse_command(command):
         if not command or not command.strip():
             raise ScriptException("Empty script command.")
-        if os.name == "nt":  # Windows: escape all backslashes in the path.
+        # Windows: escape all backslashes in the path.
+        if os.name == "nt":  # pragma: no cover
             backslashes = shlex.split(command, posix=False)[0].count("\\")
             command = command.replace("\\", "\\\\", backslashes)
         args = shlex.split(command)  # pragma: nocover
@@ -71,10 +75,15 @@ class Script(object):
         self.ns = {'__file__': os.path.abspath(self.args[0])}
         sys.path.append(script_dir)
         try:
-            execfile(self.args[0], self.ns, self.ns)
+            with open(self.filename) as f:
+                code = compile(f.read(), self.filename, 'exec')
+                exec (code, self.ns, self.ns)
         except Exception as e:
-            # Python 3: use exception chaining, https://www.python.org/dev/peps/pep-3134/
-            raise ScriptException(traceback.format_exc(e))
+            six.reraise(
+                ScriptException,
+                ScriptException(str(e)),
+                sys.exc_info()[2]
+            )
         finally:
             sys.path.pop()
         return self.run("start", self.args)
@@ -103,6 +112,10 @@ class Script(object):
             try:
                 return f(self.ctx, *args, **kwargs)
             except Exception as e:
-                raise ScriptException(traceback.format_exc(e))
+                six.reraise(
+                    ScriptException,
+                    ScriptException(str(e)),
+                    sys.exc_info()[2]
+                )
         else:
             return None
diff --git a/test/mitmproxy/tutils.py b/test/mitmproxy/tutils.py
index 791db6d9e..191eb9665 100644
--- a/test/mitmproxy/tutils.py
+++ b/test/mitmproxy/tutils.py
@@ -3,7 +3,7 @@ import shutil
 import tempfile
 import argparse
 import sys
-from cStringIO import StringIO
+from six.moves import cStringIO as StringIO
 from contextlib import contextmanager
 
 from unittest.case import SkipTest