You can do lots of really cool things with aliases! I just use them for insert text though!!

/alias add [alias] /input insert [text] will setup an alias that will be insert into text input box when typing /[alias]

/alias add shrug /input insert ¯\_(ツ)_/¯

• Alias examples on Weechat's Github wiki.
• Alias section in the Weechat User's Guide.

Some character changes:

/set weechat.look.prefix_error "⚠"
/set weechat.look.prefix_network ""
/set weechat.look.prefix_same_nick "” "
/set weechat.look.prefix_join "--→"
/set weechat.look.prefix_quit "←--"

Bars:

/set weechat.bar.title.color_bg [number or name]
/set weechat.bar.title.color_fg [number or name]

/set weechat.bar.status.color_bg
/set weechat.bar.status.color_fg

(add column to the left that features buffers. In place of bufferlist.pl plugin below.

/bar add buffers window 22 1 [things to add to bar]

There's actually a built-in way to connect to Slack via IRC, but there's also a Python plug-in which is more full-featured called wee-slack. And since Slack's IRC bridge has now been closed this is one of the few ways to use Slack in another client.

• wee-slack/wee-slack
• WeeChat#Native_client
  • (needs python2-websocket-client-pebble)

• WeeChat user’s guide (English, lots of languages availible though).
• FiXato's guide to WeeChat.
• WeeChat on the Arch wiki.
• Advanced Weechat on the Oregan State University Linux User Group website.