Thank you Bertrand for the input. With respect to Slack and how this project uses it, I think I can make the case that it fits the criteria you quoted from Mark Thomas.
> ...The criteria that the ASF looks for in communication channels used by projects are (in no particular order): > - open to all Our self-signup is fully automated and open to all. Unlike other projects which send requests to moderators, anyone with an email id can register to join our Slack and is admitted automatically. Our #general channel --- which is where the majority of public discussion happens --- links to the project's code of conduct as well. > - asynchronous Slack does the give the impression of synchronicity which is why I think it's probably preferred --- As in, if one has a question and wants an answer quickly, it's more likely they will try slack (or gasp, twitter). But there is often asynchronous communication also happening on Slack and i think it's detrimental to people's well-being to treat Slack as a fully synchronous medium. Anyway, I'm tending toward different topics now but I just wanted to point out that there are plenty of cases in our Slack where questions aren't always answered "immediately" and might take a few hours or even a day. > - available off-line This is perhaps too nuanced -- the Slack client will generally allow you to read messages when disconnected, and if you receive Slack notifications by email, and your email is also available offline, then it also works. Is that satisfactory? The daily digests we've automated also provide another way to consume the messages off-line. > - full history We only recently started sending our daily slack digests to our Apache dev list. But I can replay the digests from the very first day we started using the current Slack for the project. If there's value in that, I'm happy to do it, but perhaps consolidate the historical digest into a single large email to avoid a thousand emails being sent (or use a different target list to reduce the noise). > - searchable > - archived on ASF controlled systems The Slack daily digests are searchable and archived in the way our dev list is searchable. > - low bandwidth / minimal system requirements ... Heh - I guess there are some stories about Slack being a CPU hog sometimes. To your comment that: Slack is central to the project and one cannot really get involved without being active there "all the time". I think it will serve us well to avoid this misconception --- certainly that is NOT the case in my opinion and no one should be expected to be active in Slack all the time. Thank you for the advice for establishing better guidelines on the communication channels, I very much like the suggestions and support us addressing these concerns. -r