Announcing a Julia Slack


Hi all,
We now have a Slack group for talking about Julia at Anyone in good standing with the Julia community is welcome to join by filling out the form at (now Topics include general discussion of Julia and different areas of the Julia ecosystem, organized by channel.


  • Behavior in the Slack is subject to the Julia code of conduct.
  • The Slack is not a place to harass contributors and package authors with questions easily answered via documentation. Limit your use of pings and direct messages and generally be respectful of the time of others, none of whom are obligated to answer questions.
  • Anyone who is generally disruptive on public channels in the Slack can be warned and asked to leave the Slack.


Fourth Weekly Upgradathon Friday TODAY (July 20, 2018)

How is this different from the Julialang Gitter channel (and associated project channels)? The main channel also enjoys a bridge to IRC. I love open communication but sometimes there are too many channels.


People who prefer to use Gitter, IRC, or what have you can continue to do so. We’ve set up this Slack as a more or less “official” channel for more casual conversation than what’s within the scope of GitHub or Discourse, with close moderation and enforcement of the Julia code of conduct. We don’t expect it to entirely replace existing channels; in the end, you can chat wherever you feel most comfortable chatting. :slight_smile:


These two things seem to be at odds:

for more casual conversation than what’s within the scope of GitHub or Discourse,

with close moderation and enforcement of the Julia code of conduct.

As a package developer, I don’t want to miss any opportunities to help, but with Github issues, discourse, stack overflow, and 3 channels on gitter,I have enough things to monitor right now (and, truth be told, I’m not a huge fan of moderated communication.)

Perhaps I can ask a favor of anyone who’s going to be regular in Slack: point anyone who’s looking for JuliaGraphs help back to one of the above resources, please?


I apologize if that came across as self-contradictory. We simply expect the conversation that takes place in the Slack to remain respectful and within the terms of our code of conduct. Often that happens naturally in communication forums, but not always. We want to ensure that this Slack is a place where participants can expect to be treated with respect.

Anyway, Slack history is ephemeral; it’s generally better for people to get help here in Discourse, our dedicated discussion forum. Slack is better for casual side conversations and quick questions, akin to Gitter or IRC.

You are of course welcome to encourage users of your packages to seek help through whatever channel you find most appropriate; we don’t expect you to spend time monitoring every possible medium in which a Julia discussion can take place. The Slack will be here if you want it, and if not that’s okay too.


Thanks - I appreciate the clarification and am saddened that respectful conversation isn’t a given these days.

I do worry that we’re fragmenting the great discussion among the user community by using two completely disparate real-time chat systems. My preference would be to pick one and stick with it, even if it’s not the one I prefer.


Well, the main difference of Slack from Gitter is that Slack requires invites, while anyone can join a Gitter. This is one reason why the first JuliaLang slack didn’t go anywhere: initial people joined but then no one else did.

Given that difference between Slack and Gitter, I find it usually means that there’s less “drop-ins” coming to Slack channels. The Gitter channel gets a lot of new people who don’t even have an account: they just use a Twitter account or ask a question on IRC and we chime in. I wouldn’t expect that on Slack: everyone there will have sought out an invite. This has its ups and downs. The ups is it looks like more core devs are on Slack. Also, some people I know can get permission to use Slack at work but can’t get permission for Gitter. The downside is that of course it’s harder to find.

Never forget “Is Julia good for AI?” botspam, and @musm’s meme picture for that of course. It happens and it needs to be stated.


Here’s one comparison. I’ve never been a big fan of Gitter’s unreliable interface, but at least it has support for Markdown (which Slack hasn’t?).


No, Slack does support some dialect of Markdown. The one thing I’d probably miss over gitter is inline LaTeX, which doesn’t work very well in Slack afaik.


That’s good to know. I just did a quick search and found the official Slack response:

Though we understand many people would love to use Markdown in Slack messages, we have no plans to support it.

but perhaps that’s a dated response.


In good standing means that the group is closed and admission is the exception or everybody is admitted except special “not good standing” cases?


I’m a little puzzled by this move, to be honest.

Unlike Slack, Gitter is open source, doesn’t have archive limits (Slack does in the free version), has open logs that are accessible online (for open channels, but it also supports private channels, if that’s a concern), and has a sane unified account system (whereas for Slack you have to create a separate account for each community you join). Not to mention many people in the community used Gitter already.

I’m wondering if there was an objective pros/cons analysis that determined that Slack was more appropriate than Gitter to fill the official “informal chat” slot in the Julia community, or whether it was chosen simply because most core devs were on Slack already.


There was an extended discussion among committers who use chat programs. Several people wanted Mattermost or Gitter, but basically: no one wants to be responsible for running Mattermost, and Gitter’s chat interface (the primary function) leaves much to be desired – I’ve tried to use it many times, but only last a couple days at a go because the scrolling is very rough. Gitter also lacks emoji responses, which are strangely, surprisingly effective at increasing the nuance and density of conversation without increasing the spew rate. I’m not sure what level of “objective” that meets, but there it is. I and others probably agree with you on some principles, but ultimately it comes down to what enough people are willing to use. The history question was a relatively minor concern because part of the point is (at least nominal) ephemerality; it remains to be seen whether the 10k limit will be workable if the slack gets very busy.


The latter.