Hi @hmhealey, many thanks for that, this is a key factor for us moving to Mattermost, we’d really like to hear that it’s on it’s way.
On another note, if you need something to test it on then there is a lita-slack plugin for the Lita chat bot that is ready to go with slack’s RTM API. I would assume if you wanted to replicate the exact same API calls that Slack has and that are used by this plugin in your first version of the API, then that would be a very good start. Any Lita-Mattermost plugin that pops up as a result of this testing would be wonderful too ;).