Ask HN: Build your own chat service or buy?

From what I understand you are talking about an chat inside your app, and not a chat for your company (like matrix or Slack).

I would say it depends.

If you know how to implement long polling then making a simple chat is not hard, the hardest part, being certainly the UI, but it can be improved over time. The only thing to remember is to sanitize and check all the input data, as a chat is basically moving untrusted data from user A to user B. A lot of in-house built chat systems are vulnerable to XSS and other injection attacks.

Otherwise, I've never used it, but I believe that a service such as https://pusher.com/ would make it.

Worked for a startup making their own chat and it sucked up such a lot of effort on everyone's part trying to get all the tiny details working that everything else started to suffer.

I dunno though - even using something like Mattermost as the backend, you're probably still having to do a lot of UI work yourself as a wrapper around that. Damned if you do, damned if you don't?

I'd buy. Unless chat is core to the functionality of what you're building, why would you re-invent the wheel?

If you just want something private for yourself and a few of your friends nextcloud talk is pretty good.