I'm a grumpy linux greybeard type, so I went with... plain text files.
Everything is deployed via docker, so I've got a docker-compose.yml for each stack, and any notes or configuration things specific to that app is a comment in the compose file. Those are all backed up in a couple of places, since all I need to do is drop them on a filesystem, and bam, complete restoration.
Reverse proxy is nginx, because it's reliable, tested, proven, works, and while it might not have all those fancy auto-config options other things have, it also doesn't automatically configure itself into a way that I'd prefer it didn't, either.
I don't use any tools like portainer or dockge or nginx proxy manager at this point, because dealing with what's just a couple of config files on the filesystem is faster (for me) and less complicated (again, for me) than adding another layer of software on top (and it keeps your attack surface small).
My one concession to gui shit for the docker is an install of dozzle because it certainly makes dealing with docker logs simple, and it simplifies managing the ~40 stacks and ~85 containers that I've got setup at the moment.