diff --git a/.gitignore b/.gitignore
index eec5d01c8..94bbf4167 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,8 +1,9 @@
 *.pyc
-.cache
 .idea
 dist
+build
 slackclient.egg-info
+.cache
 *.log
 env
 .tox
diff --git a/slackclient/_client.py b/slackclient/_client.py
index 03bbeb433..9a2f36cf2 100644
--- a/slackclient/_client.py
+++ b/slackclient/_client.py
@@ -176,6 +176,9 @@ def process_changes(self, data):
             if data["type"] == "team_join":
                 user = data["user"]
                 self.server.parse_user_data([user])
+            if data["type"] == 'group_joined':
+                channel = data["channel"]
+                self.server.attach_channel(channel["name"], channel["id"], [])
             pass