diff --git a/docs/conf.py b/docs/conf.py
index 54dc0d7a..ae0f1aa9 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -12,8 +12,6 @@
 # serve to show the default.
 
 import sys, os
-from webassets.six.moves import map
-from webassets.six.moves import zip
 
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
diff --git a/examples/appengine/helloworld.py b/examples/appengine/helloworld.py
index d8f4fdb3..bc236f69 100644
--- a/examples/appengine/helloworld.py
+++ b/examples/appengine/helloworld.py
@@ -1,8 +1,3 @@
-from __future__ import print_function
-from __future__ import print_function
-from __future__ import print_function
-from __future__ import print_function
-from __future__ import print_function
 # Import assets configuration
 from assets import bundle
 
diff --git a/src/webassets/bundle.py b/src/webassets/bundle.py
index bbb23d8e..547cf4c3 100644
--- a/src/webassets/bundle.py
+++ b/src/webassets/bundle.py
@@ -2,8 +2,6 @@
 import os
 from os import path
 from webassets import six
-from webassets.six.moves import map
-from webassets.six.moves import zip
 
 from .filter import get_filter
 from .merge import (FileHunk, UrlHunk, FilterTool, merge, merge_filters,
@@ -161,12 +159,9 @@ def _set_filters(self, value):
             self._filters = ()
             return
 
-        if isinstance(value, six.string_types):
+        if isinstance(value, str):
             # 333: Simplify w/o condition?
-            if six.PY3:
-                filters = map(str.strip, value.split(','))
-            else:
-                filters = map(unicode.strip, unicode(value).split(','))
+            filters = map(str.strip, value.split(','))
         elif isinstance(value, (list, tuple)):
             filters = value
         else:
@@ -276,7 +271,7 @@ def _filter_duplicates(resolved):
     def _get_depends(self):
         return self._depends
     def _set_depends(self, value):
-        self._depends = [value] if isinstance(value, six.string_types) else value
+        self._depends = [value] if isinstance(value, str) else value
         self._resolved_depends = None
     depends = property(_get_depends, _set_depends, doc=
     """Allows you to define an additional set of files (glob syntax
diff --git a/src/webassets/env.py b/src/webassets/env.py
index 90b8cd0e..14126767 100644
--- a/src/webassets/env.py
+++ b/src/webassets/env.py
@@ -1,8 +1,6 @@
 import os
 from os import path
 from itertools import chain
-from webassets import six
-from webassets.six.moves import map
 from webassets.utils import is_url
 
 try:
@@ -242,7 +240,7 @@ def resolve_source(self, ctx, item):
         """
 
         # Pass through some things unscathed
-        if not isinstance(item, six.string_types):
+        if not isinstance(item, str):
             # Don't stand in the way of custom values.
             return item
         if is_url(item) or path.isabs(item):
@@ -308,7 +306,7 @@ def __init__(self):
         self._anon_bundles = []
 
     def __iter__(self):
-        return chain(six.itervalues(self._named_bundles), self._anon_bundles)
+        return chain(self._named_bundles.values(), self._anon_bundles)
 
     def __getitem__(self, name):
         return self._named_bundles[name]
diff --git a/src/webassets/ext/jinja2.py b/src/webassets/ext/jinja2.py
index defeb9e7..723ab758 100644
--- a/src/webassets/ext/jinja2.py
+++ b/src/webassets/ext/jinja2.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import
-
 import warnings
 import jinja2
 from jinja2.ext import Extension
diff --git a/src/webassets/filter/__init__.py b/src/webassets/filter/__init__.py
index 44280c3e..409a7970 100644
--- a/src/webassets/filter/__init__.py
+++ b/src/webassets/filter/__init__.py
@@ -2,8 +2,6 @@
 contents (think minification, compression).
 """
 
-from __future__ import with_statement
-
 import os
 import subprocess
 import inspect
@@ -11,8 +9,6 @@
 import tempfile
 import pkgutil
 from webassets import six
-from webassets.six.moves import map
-from webassets.six.moves import zip
 try:
     frozenset
 except NameError:
@@ -34,7 +30,7 @@ def freezedicts(obj):
     if isinstance(obj, (list, tuple)):
         return type(obj)([freezedicts(sub) for sub in obj])
     if isinstance(obj, dict):
-        return frozenset(six.iteritems(obj))
+        return frozenset(obj.items())
     return obj
 
 
@@ -50,19 +46,11 @@ def smartsplit(string, sep):
     be done.
     """
     assert string is not None   # or shlex will read from stdin
-    if not six.PY3:
-        # On 2.6, shlex fails miserably with unicode input
-        is_unicode = isinstance(string, unicode)
-        if is_unicode:
-            string = string.encode('utf8')
     l = shlex.shlex(string, posix=True)
     l.whitespace += ','
     l.whitespace_split = True
     l.quotes = ''
-    if not six.PY3 and is_unicode:
-        return map(lambda s: s.decode('utf8'), list(l))
-    else:
-        return list(l)
+    return list(l)
 
 
 class option(tuple):
@@ -204,9 +192,6 @@ def get_config(self, setting=False, env=None, require=True,
         if value is None and not env is False:
             value = os.environ.get(env)
             if value is not None:
-                if not six.PY3:
-                    # TODO: What charset should we use? What does Python 3 use?
-                    value = value.decode('utf8')
                 if type == list:
                     value = smartsplit(value, ',')
 
@@ -623,7 +608,7 @@ def get_filter(f, *args, **kwargs):
         # Don't need to do anything.
         assert not args and not kwargs
         return f
-    elif isinstance(f, six.string_types):
+    elif isinstance(f, str):
         if f in _FILTERS:
             klass = _FILTERS[f]
         else:
diff --git a/src/webassets/filter/autoprefixer.py b/src/webassets/filter/autoprefixer.py
index a406c30f..a85c7b1d 100644
--- a/src/webassets/filter/autoprefixer.py
+++ b/src/webassets/filter/autoprefixer.py
@@ -1,5 +1,3 @@
-from __future__ import with_statement
-
 from webassets.filter import ExternalTool
 from webassets.utils import working_directory
 
diff --git a/src/webassets/filter/clevercss.py b/src/webassets/filter/clevercss.py
index 37ef78e7..5c92718b 100644
--- a/src/webassets/filter/clevercss.py
+++ b/src/webassets/filter/clevercss.py
@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 from webassets.filter import Filter
 
 
diff --git a/src/webassets/filter/closure.py b/src/webassets/filter/closure.py
index 76435e2e..7c0e7f02 100644
--- a/src/webassets/filter/closure.py
+++ b/src/webassets/filter/closure.py
@@ -30,7 +30,6 @@
         ['--output_wrapper', 'foo: %output%']
 """
 
-from __future__ import absolute_import
 from webassets.filter import JavaTool
 
 
diff --git a/src/webassets/filter/coffeescript.py b/src/webassets/filter/coffeescript.py
index 9ff075d3..c530040a 100644
--- a/src/webassets/filter/coffeescript.py
+++ b/src/webassets/filter/coffeescript.py
@@ -1,4 +1,3 @@
-from __future__ import print_function
 import os, subprocess
 
 from webassets.filter import Filter
diff --git a/src/webassets/filter/cssmin.py b/src/webassets/filter/cssmin.py
index bf0c4a26..8d1a333f 100644
--- a/src/webassets/filter/cssmin.py
+++ b/src/webassets/filter/cssmin.py
@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 from webassets.filter import Filter
 
 
diff --git a/src/webassets/filter/cssprefixer.py b/src/webassets/filter/cssprefixer.py
index 59cffbbe..483e6e5a 100644
--- a/src/webassets/filter/cssprefixer.py
+++ b/src/webassets/filter/cssprefixer.py
@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 from webassets.filter import Filter
 
 
diff --git a/src/webassets/filter/cssrewrite/urlpath.py b/src/webassets/filter/cssrewrite/urlpath.py
index f768da59..13e04b5f 100644
--- a/src/webassets/filter/cssrewrite/urlpath.py
+++ b/src/webassets/filter/cssrewrite/urlpath.py
@@ -18,7 +18,6 @@
 # Scripts maintained at http://www.voidspace.org.uk/python/index.shtml
 # E-mail fuzzyman@voidspace.org.uk
 
-from __future__ import print_function
 import posixpath
 import os
 try:
diff --git a/src/webassets/filter/cssutils.py b/src/webassets/filter/cssutils.py
index 2b8f4a11..8ad8f556 100644
--- a/src/webassets/filter/cssutils.py
+++ b/src/webassets/filter/cssutils.py
@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 import logging
 import logging.handlers
 
diff --git a/src/webassets/filter/jade.py b/src/webassets/filter/jade.py
index 16bab7d9..0acb5c63 100644
--- a/src/webassets/filter/jade.py
+++ b/src/webassets/filter/jade.py
@@ -1,6 +1,5 @@
 # coding=utf-8
 
-from __future__ import print_function
 import os, subprocess
 from webassets.filter import Filter, register_filter
 from webassets.exceptions import FilterError
diff --git a/src/webassets/filter/jinja2.py b/src/webassets/filter/jinja2.py
index 50a295ea..c13c13a3 100644
--- a/src/webassets/filter/jinja2.py
+++ b/src/webassets/filter/jinja2.py
@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 from webassets.filter import Filter
 
 
diff --git a/src/webassets/filter/jsmin.py b/src/webassets/filter/jsmin.py
index ff21d7f9..83b9198e 100644
--- a/src/webassets/filter/jsmin.py
+++ b/src/webassets/filter/jsmin.py
@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 import warnings
 
 from webassets.filter import Filter
diff --git a/src/webassets/filter/jspacker/jspacker.py b/src/webassets/filter/jspacker/jspacker.py
index e6815310..e2ce4b22 100644
--- a/src/webassets/filter/jspacker/jspacker.py
+++ b/src/webassets/filter/jspacker/jspacker.py
@@ -1,4 +1,3 @@
-from __future__ import print_function
 ##  ParseMaster, version 1.0 (pre-release) (2005/05/12) x6
 ##  Copyright 2005, Dean Edwards
 ##  Web: http://dean.edwards.name/
@@ -9,11 +8,6 @@
 ##  Ported to Python by Florian Schulze
 
 import os, re
-import sys
-if sys.version < '3':
-    integer_types = (int, long,)
-else:
-    integer_types = (int,)
 
 # a multi-pattern parser
 
@@ -111,7 +105,7 @@ def _replacement(self, match):
                 replacement = pattern.replacement
                 if callable(replacement):
                     return replacement(match, i)
-                elif isinstance(replacement, integer_types):
+                elif isinstance(replacement, int):
                     return match.group(replacement+i)
                 else:
                     return replacement
diff --git a/src/webassets/filter/less.py b/src/webassets/filter/less.py
index c228e3ef..84a304b8 100644
--- a/src/webassets/filter/less.py
+++ b/src/webassets/filter/less.py
@@ -1,5 +1,3 @@
-from __future__ import with_statement
-
 import os
 
 from webassets.filter import ExternalTool
diff --git a/src/webassets/filter/libsass.py b/src/webassets/filter/libsass.py
index 6867be32..29412d28 100644
--- a/src/webassets/filter/libsass.py
+++ b/src/webassets/filter/libsass.py
@@ -6,9 +6,6 @@
 [1] https://bitbucket.org/jhuss/webassets-libsass
 """
 
-from __future__ import print_function
-from __future__ import absolute_import
-
 from webassets.filter import Filter
 
 
diff --git a/src/webassets/filter/postcss.py b/src/webassets/filter/postcss.py
index 479402b5..5a11223b 100644
--- a/src/webassets/filter/postcss.py
+++ b/src/webassets/filter/postcss.py
@@ -1,5 +1,3 @@
-from __future__ import with_statement
-
 from webassets.filter import ExternalTool
 from webassets.utils import working_directory
 
diff --git a/src/webassets/filter/rcssmin.py b/src/webassets/filter/rcssmin.py
index b76325c8..43ac2786 100644
--- a/src/webassets/filter/rcssmin.py
+++ b/src/webassets/filter/rcssmin.py
@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 from webassets.filter import Filter
 
 
diff --git a/src/webassets/filter/requirejs.py b/src/webassets/filter/requirejs.py
index 536a0e3c..6e01a4db 100644
--- a/src/webassets/filter/requirejs.py
+++ b/src/webassets/filter/requirejs.py
@@ -1,5 +1,3 @@
-from __future__ import with_statement
-
 import shlex
 from os import path, getcwd
 
diff --git a/src/webassets/filter/rjsmin/__init__.py b/src/webassets/filter/rjsmin/__init__.py
index ff32865b..887c673a 100644
--- a/src/webassets/filter/rjsmin/__init__.py
+++ b/src/webassets/filter/rjsmin/__init__.py
@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 try:
     import rjsmin
 except ImportError:
diff --git a/src/webassets/filter/sass.py b/src/webassets/filter/sass.py
index 02854d6f..852dd4b3 100644
--- a/src/webassets/filter/sass.py
+++ b/src/webassets/filter/sass.py
@@ -1,5 +1,3 @@
-from __future__ import print_function
-
 import os
 
 from webassets.filter import ExternalTool
diff --git a/src/webassets/filter/sass_ruby.py b/src/webassets/filter/sass_ruby.py
index 63b07b02..c3841542 100644
--- a/src/webassets/filter/sass_ruby.py
+++ b/src/webassets/filter/sass_ruby.py
@@ -1,4 +1,3 @@
-from __future__ import print_function
 import os, subprocess
 
 from webassets.filter import ExternalTool
diff --git a/src/webassets/filter/slimit.py b/src/webassets/filter/slimit.py
index 0b8fae0b..bf7661ad 100644
--- a/src/webassets/filter/slimit.py
+++ b/src/webassets/filter/slimit.py
@@ -1,4 +1,3 @@
-from __future__ import absolute_import
 from webassets.filter import Filter
 
 
diff --git a/src/webassets/filter/slimmer.py b/src/webassets/filter/slimmer.py
index 7e98bfd7..104ba263 100644
--- a/src/webassets/filter/slimmer.py
+++ b/src/webassets/filter/slimmer.py
@@ -1,5 +1,3 @@
-from __future__ import absolute_import
-
 from webassets.filter import Filter
 
 
diff --git a/src/webassets/filter/spritemapper.py b/src/webassets/filter/spritemapper.py
index 8ee84650..6b30c062 100644
--- a/src/webassets/filter/spritemapper.py
+++ b/src/webassets/filter/spritemapper.py
@@ -1,5 +1,3 @@
-from __future__ import print_function
-from __future__ import absolute_import
 from webassets.six import StringIO
 from contextlib import contextmanager
 from webassets.filter import Filter
diff --git a/src/webassets/merge.py b/src/webassets/merge.py
index 3d70bffb..3bbe28d8 100644
--- a/src/webassets/merge.py
+++ b/src/webassets/merge.py
@@ -1,6 +1,5 @@
 """Contains the core functionality that manages merging of assets.
 """
-from __future__ import with_statement
 import contextlib
 
 try:
diff --git a/src/webassets/script.py b/src/webassets/script.py
index 102a4217..65b56d78 100644
--- a/src/webassets/script.py
+++ b/src/webassets/script.py
@@ -1,4 +1,3 @@
-from __future__ import print_function
 import shutil
 import os, sys
 import time
diff --git a/src/webassets/test.py b/src/webassets/test.py
index 359aef50..4e6bb028 100644
--- a/src/webassets/test.py
+++ b/src/webassets/test.py
@@ -3,7 +3,6 @@
 This is included in the webassets package because it is useful for testing
 external libraries that use webassets (like the flask-assets wrapper).
 """
-from __future__ import print_function
 
 import tempfile
 import shutil
@@ -12,8 +11,6 @@
 import time
 
 from webassets import Environment, Bundle
-from webassets.six.moves import map
-from webassets.six.moves import zip
 
 
 __all__ = ('TempDirHelper', 'TempEnvironmentHelper',)
diff --git a/src/webassets/updater.py b/src/webassets/updater.py
index 0153cc7a..3347ebe5 100644
--- a/src/webassets/updater.py
+++ b/src/webassets/updater.py
@@ -26,9 +26,6 @@
 increase as using the hash to reliably determine which bundles to skip.
 """
 
-from webassets import six
-from webassets.six.moves import map
-from webassets.six.moves import zip
 from webassets.exceptions import BundleError, BuildError
 from webassets.utils import RegistryMetaclass, is_url, hash_func
 
@@ -48,9 +45,9 @@
 """
 
 
-class BaseUpdater(six.with_metaclass(RegistryMetaclass(
+class BaseUpdater(metaclass=RegistryMetaclass(
     clazz=lambda: BaseUpdater, attribute='needs_rebuild',
-    desc='an updater implementation'))):
+    desc='an updater implementation')):
     """Base updater class.
 
     Child classes that define an ``id`` attribute are accessible via their
diff --git a/src/webassets/version.py b/src/webassets/version.py
index 5bb71607..70d51771 100644
--- a/src/webassets/version.py
+++ b/src/webassets/version.py
@@ -2,8 +2,6 @@
 implementations.
 """
 
-from __future__ import with_statement
-
 import os
 import pickle
 from webassets import six
diff --git a/tests/helpers.py b/tests/helpers.py
index e8991630..04102170 100644
--- a/tests/helpers.py
+++ b/tests/helpers.py
@@ -1,4 +1,3 @@
-from __future__ import with_statement
 import re
 
 from webassets.test import TempDirHelper, TempEnvironmentHelper
diff --git a/tests/test_bundle_urls.py b/tests/test_bundle_urls.py
index f40286f8..f282ea34 100644
--- a/tests/test_bundle_urls.py
+++ b/tests/test_bundle_urls.py
@@ -4,8 +4,6 @@
 more likely` found in `test_bundle_various.py``.
 """
 
-from __future__ import with_statement
-
 import re
 
 import pytest
diff --git a/tests/test_bundle_various.py b/tests/test_bundle_various.py
index aa505352..cb2ec1b2 100644
--- a/tests/test_bundle_various.py
+++ b/tests/test_bundle_various.py
@@ -3,8 +3,6 @@
 specific features/aspects, like "globbing" or "versions".
 """
 
-from __future__ import with_statement
-
 import copy
 from os import path
 import uuid
diff --git a/tests/test_cache.py b/tests/test_cache.py
index 9d67f185..7b0304e6 100644
--- a/tests/test_cache.py
+++ b/tests/test_cache.py
@@ -1,5 +1,3 @@
-from __future__ import with_statement
-
 import random
 import pytest
 
diff --git a/tests/test_environment.py b/tests/test_environment.py
index ff362896..453ce04f 100644
--- a/tests/test_environment.py
+++ b/tests/test_environment.py
@@ -1,5 +1,3 @@
-from __future__ import with_statement
-
 import os
 
 import pytest
diff --git a/tests/test_filters.py b/tests/test_filters.py
index f38bcc01..b128fc44 100644
--- a/tests/test_filters.py
+++ b/tests/test_filters.py
@@ -1,7 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import print_function
-from __future__ import with_statement
-
 import os
 import os.path
 import shutil
diff --git a/tests/test_loaders.py b/tests/test_loaders.py
index 3f97d58a..438f507d 100644
--- a/tests/test_loaders.py
+++ b/tests/test_loaders.py
@@ -1,4 +1,3 @@
-from __future__ import with_statement
 import sys
 
 import pytest
diff --git a/tests/test_script.py b/tests/test_script.py
index d5d3bc94..7ebcbe83 100644
--- a/tests/test_script.py
+++ b/tests/test_script.py
@@ -4,8 +4,6 @@
 I wonder whether I shouldn't just do full-stack tests here instead of mocking.
 """
 
-from __future__ import with_statement
-
 import logging
 from threading import Thread, Event