The thing that annoy me the most with C2 is that almost each time I googled Smalltalk when I wasstill a beginner with Pharo and Smalltalk this came up often
http://wiki.c2.com/?WhyIsSmalltalkDeadBut yes I agree, its nice to have a place to put information and never worry about it getting delete.
On the matter of Slack, my Discord bot , lighthouse has evolved to message the online chat with replies to the mailing list which gave a good look inside how chat bots work. Esteban made me admin in Slack so the next step is to have the bot connect to Slack and copy the Slack messages to Discord chat , which means you wont need a Slack plan, because Discord never deletes messages. This way we can use Discord as a backup for our Slack messages and the bot could also copy the messages to a file , I am considering SQLite which we support, so that we never lose the content.
Problem solved and it also solves the problem of fragmentation. The mailing list is already connected to Discord via my bot, Slack will also connect to discord via my bot and pretty much anything else can be brought into this hub so everyone can keep using Slack or whatever way he or she prefers to communicate without the fear of fragmentation.