diff --git a/tests/test_http.py b/tests/test_http.py
index f0e39310..2c3c8b2d 100644
--- a/tests/test_http.py
+++ b/tests/test_http.py
@@ -13,7 +13,7 @@
 thriftpy2.install_import_hook()  # noqa
 
 from thriftpy2.http import make_server, make_client, client_context  # noqa
-from thriftpy2.thrift import TApplicationException
+from thriftpy2.thrift import TApplicationException # noqa
 
 
 addressbook = thriftpy2.load(os.path.join(os.path.dirname(__file__),
diff --git a/thriftpy2/thrift.py b/thriftpy2/thrift.py
index 381595a1..92cbb8fc 100644
--- a/thriftpy2/thrift.py
+++ b/thriftpy2/thrift.py
@@ -68,9 +68,26 @@ def __init__(self):
             pass
         return __init__
 
-    varnames, defaults = zip(*spec)
+    if hasattr(cls, 'thrift_spec'):
+        args = []
+        kwargs = []
+        varnames = []
+        defaults = []
+        for spec_element, t_spec in zip(spec, cls.thrift_spec.values()):
+            varnames.append(spec_element[0])
+            if t_spec[-1]:
+                args.append(spec_element[0])
+            else:
+                kwargs.append(spec_element)
+                defaults.append(spec_element[1])
+        defaults = tuple(defaults) if defaults else None
+
+        args.extend(map('{0[0]}={0[1]!r}'.format, kwargs))
+        args = ', '.join(args)
+    else:
+        varnames, defaults = zip(*spec)
+        args = ', '.join(map('{0[0]}={0[1]!r}'.format, spec))
 
-    args = ', '.join(map('{0[0]}={0[1]!r}'.format, spec))
     init = "def __init__(self, {}):\n".format(args)
     init += "\n".join(map('    self.{0} = {0}'.format, varnames))