[MisterKent]

Agree with the above, except:

Sharing solutions in slack works until stuff becomes impossible to find.

Using confluence or some type of team documentation feature can help with that stuff. Better yet, keep it very low effort to add docs there, so people can copy paste important (long lived) messages there.

[rglullis]

Yes, I think I mentioned this before: we had similar issues on our team and I was tasked with improving intra- and inter-team communication.

The solution we adopted was to create a Confluence space for each team, and any question on Slack would have to be in the form of "Where on Confluence can I find the information about <thing I need to learn>?"

This very quickly made all team leads responsible for documentation and for keeping things up-to-date. If no page about <thing I need to learn> existed, then the lead would have to create the minimal page even if just to answer the question on Slack and respond with the Confluence link. Once you have the link, people would use the comment page to ask for clarifications/details, and we would "resolve" the comments as soon as the page was updated.

Maybe it's because I am big fan of wikis, but to me this worked quite well.