https://github.com/wee-slack/wee-slack
Background
I'm not associated but I thought I had to share this. Since about a year back I've migrated to wee-slack for slack usage in my WeeChat IRC-client, it's also possible to use WeeChat as a bouncer through WeeChat relay (if not mistaken there's irssi-proxy:esque proxy-plugin too).
I've been a die hard irssi-fan and still use it for much of my IRC interaction and been using weechat as a irssi-like slack client. As a bonus we can use many of the features that didn't work through the irc-gateway.
You can also see a preview of my setup on my twitter
https://twitter.com/ahultner/status/923588418126348289
If you're interested of my personal setup you can find it in my dotfiles
https://github.com/Hultner/dotfiles/tree/master/cetrezMBP/.w...