Right now that is a bit of a sticking point with Lemmy. Right now, as far as I can tell, none of the apps for lemmy really do discovery.

If you are on an instance with a large amount of people, the easiest way is probably your instance’s communities list. This can be found by going to your lemmy instances web domain (in your case programming.dev) and log in. On desktop it will just show a little “communities” link in the top left you can click on, on the mobile site you have to tap trending -> explore communities.

What this “communities” list does is list every community that anyone on your instance has subscribed to. Subscriber and daily active user numbers may not be accurate as they as far as I can tell only count your instance’s users.

What I did when I first started lemmy was go through this list and subscribe to any community that remotely interested me.

The place where you will be able to see the absolute most number of communities is a lemmy indexer like lemmyverse which lists almost all instances and has all of their communities listed.

Other than that, though, I think discoverability is something actively being developed on the lemmy platform.

Hope this was helpful and you enjoy your time here o7