[walrus01]

And even more so to the point, you can't self host slack and have absolute root level to the OS it's running on admin control. For somebody who knows what's they're doing it takes maybe 45 minutes to set up a basic ircd-hybrid daemon on Debian or centos.

[AnIdiotOnTheNet]

If you use a high level language like Python you could almost write an IRC server in 45 minutes.