diff --git a/.travis.yml b/.travis.yml
index b1883254..0e17587e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,6 +5,7 @@ python:
   - 3.2
   - 3.3
   - 3.4
+  - nightly
   - pypy
   - pypy3
 install:
diff --git a/pep8.py b/pep8.py
index 4d993dab..34ce07ae 100755
--- a/pep8.py
+++ b/pep8.py
@@ -1314,6 +1314,13 @@ def _is_eol_token(token, _eol_token=_is_eol_token):
 _checks = {'physical_line': {}, 'logical_line': {}, 'tree': {}}
 
 
+def _get_parameters(function):
+    if sys.version_info >= (3, 3):
+        return list(inspect.signature(function).parameters)
+    else:
+        return inspect.getargspec(function)[0]
+
+
 def register_check(check, codes=None):
     """Register a new check object."""
     def _add_check(check, kind, codes, args):
@@ -1322,13 +1329,13 @@ def _add_check(check, kind, codes, args):
         else:
             _checks[kind][check] = (codes or [''], args)
     if inspect.isfunction(check):
-        args = inspect.getargspec(check)[0]
+        args = _get_parameters(check)
         if args and args[0] in ('physical_line', 'logical_line'):
             if codes is None:
                 codes = ERRORCODE_REGEX.findall(check.__doc__ or '')
             _add_check(check, args[0], codes, args)
     elif inspect.isclass(check):
-        if inspect.getargspec(check.__init__)[0][:2] == ['self', 'tree']:
+        if _get_parameters(check.__init__)[:2] == ['self', 'tree']:
             _add_check(check, 'tree', codes, None)
 
 
@@ -1504,7 +1511,7 @@ def check_ast(self):
         """Build the file's AST and run all AST checks."""
         try:
             tree = compile(''.join(self.lines), '', 'exec', PyCF_ONLY_AST)
-        except (SyntaxError, TypeError):
+        except (ValueError, SyntaxError, TypeError):
             return self.report_invalid_syntax()
         for name, cls, __ in self._ast_checks:
             checker = cls(tree, self.filename)
diff --git a/testsuite/test_api.py b/testsuite/test_api.py
index 341fb34b..1cb0d4b5 100644
--- a/testsuite/test_api.py
+++ b/testsuite/test_api.py
@@ -339,6 +339,9 @@ def test_check_nullbytes(self):
         if 'SyntaxError' in stdout:
             # PyPy 2.2 returns a SyntaxError
             expected = "stdin:1:2: E901 SyntaxError"
+        elif 'ValueError' in stdout:
+            # Python 3.5.
+            expected = "stdin:1:1: E901 ValueError"
         else:
             expected = "stdin:1:1: E901 TypeError"
         self.assertTrue(stdout.startswith(expected),