I highly recommend Coolify. I evaluated every option when looking for a Heroku alternative, and Coolify is clearly the best as long as you don’t absolutely require zero downtime deploys.
We are hosting over 100 services on it for https://hackclub.com and it’s been great. We’re 3 months in now.
The key is to think about it as a GUI on top of Docker, not as a fully managed solution.
It’s one of those PHP apps that’s weirdly reliable. I see lots of other comments recommending Dokku / Dokploy / others. None of those options are nearly as mature as Coolify in my experience.