We have a Twitter account on which we post regularly, and link to Discord is in bio.
Also we created some gamified quests with rewards that require people to join our Discord.
We've been growing the community for 2+ years, so it's a lot of commitment and consistency!
We don't have it at the moment but contemplating launching one for our existing and potential customers. Our target audience is Shopify App developers and many of them seem to like Discord. At the same time, Discord isn't the most intuitive platforms to navigate and sometimes it's being perceived as less business-focused (compared to Slack for example).
I have it, but to be honest, it took me a lot of time just to understand its rules, and it’s not that easy to use.
1.1K users:
https://discord.gg/Gh9paMbRRQ