@gvhoecke Here are a few recommendations from the people I follow.
And me 😊
The way I found interesting accounts/people was just by lurking around the local timeline for a while. You see what people on your instance are tooting, who/what they're boosting, and you end up finding some really cool stuff. Then you follow them, see who they're following, who they're boosting and so on 😉
Fosstodon is a Mastodon instance that is open to anyone who is interested in technology; particularly free & open source software.