Is Slack cloud based? If so it's a big problem for a lot of compagnies, most of them don't want to host their chat service to an external provider, that's where

Is Slack cloud based? If so it's a big problem for a lot of compagnies, most of them don't want to host their chat service to an external provider, that's where Hipchat is very useful. You can host your own server in-house.