diff --git a/dddp/accounts/ddp.py b/dddp/accounts/ddp.py
index 2863e4b..0851b7e 100644
--- a/dddp/accounts/ddp.py
+++ b/dddp/accounts/ddp.py
@@ -9,6 +9,7 @@ from binascii import Error
 import collections
 import datetime
 import hashlib
+import base64
 
 from ejson import loads, dumps
 
@@ -72,15 +73,14 @@ def iter_auth_hashes(user, purpose, minutes_valid):
     """
     now = timezone.now().replace(microsecond=0, second=0)
     for minute in range(minutes_valid + 1):
-        yield hashlib.sha1(
-            '%s:%s:%s:%s:%s' % (
-                now - datetime.timedelta(minutes=minute),
-                user.password,
-                purpose,
-                user.pk,
-                settings.SECRET_KEY,
-            ),
-        ).hexdigest()
+        _content = '%s:%s:%s:%s:%s' % (
+            now - datetime.timedelta(minutes=minute),
+            user.password,
+            purpose,
+            user.pk,
+            settings.SECRET_KEY,
+        )
+        yield hashlib.sha1(_content.encode()).hexdigest()
 
 
 def get_auth_hash(user, purpose):
@@ -97,15 +97,19 @@ def calc_expiry_time(minutes_valid):
 
 def get_user_token(user, purpose, minutes_valid):
     """Return login token info for given user."""
-    token = ''.join(
-        dumps([
-            user.get_username(),
-            get_auth_hash(user, purpose),
-        ]).encode('base64').split('\n')
+    token_json = dumps([
+        user.get_username(),
+        get_auth_hash(user, purpose),
+    ])
+    token_json_enc = token_json.encode()
+    token_json_enc_b64_multiline = base64.b64encode(token_json_enc)
+    token_json_enc_b64_singleline = "".join(
+        token_json_enc_b64_multiline.decode().split("\n")
     )
+
     return {
         'id': get_meteor_id(user),
-        'token': token,
+        'token': token_json_enc_b64_singleline,
         'tokenExpires': calc_expiry_time(minutes_valid),
     }
 
@@ -314,7 +318,7 @@ class Auth(APIMixin):
     def validated_user(cls, token, purpose, minutes_valid):
         """Resolve and validate auth token, returns user object."""
         try:
-            username, auth_hash = loads(token.decode('base64'))
+            username, auth_hash = loads(base64.b64decode(token))
         except (ValueError, Error):
             cls.auth_failed(token=token)
         try:
diff --git a/dddp/postgres.py b/dddp/postgres.py
index 419b103..71c0d33 100644
--- a/dddp/postgres.py
+++ b/dddp/postgres.py
@@ -1,6 +1,6 @@
 """Django DDP PostgreSQL Greenlet."""
 
-from __future__ import absolute_import
+
 
 import ejson
 import gevent
@@ -39,7 +39,7 @@ class PostgresGreenlet(gevent.Greenlet):
         # http://www.postgresql.org/docs/current/static/libpq-connect.html
         # section 31.1.2 (Parameter Key Words) for details on available params.
         conn_params.update(
-            async=True,
+            async_=True,
             application_name='{} pid={} django-ddp'.format(
                 socket.gethostname(),  # hostname
                 os.getpid(),  # PID
diff --git a/dddp/websocket.py b/dddp/websocket.py
index ea4a909..0f63edd 100644
--- a/dddp/websocket.py
+++ b/dddp/websocket.py
@@ -153,8 +153,8 @@ class DDPWebSocketApplication(geventwebsocket.WebSocketApplication):
         # `_tx_buffer` collects outgoing messages which must be sent in order
         self._tx_buffer = {}
         # track the head of the queue (buffer) and the next msg to be sent
-        self._tx_buffer_id_gen = itertools.cycle(irange(sys.maxint))
-        self._tx_next_id_gen = itertools.cycle(irange(sys.maxint))
+        self._tx_buffer_id_gen = itertools.cycle(irange(sys.maxsize))
+        self._tx_next_id_gen = itertools.cycle(irange(sys.maxsize))
         # start by waiting for the very first message
         self._tx_next_id = next(self._tx_next_id_gen)