Have you tried Caddy as your reverse proxy? It's much simpler compared to nginx and it has very robust, integrated LE support. It's also packaged for Debian and

Have you tried Caddy as your reverse proxy? It's much simpler compared to nginx and it has very robust, integrated LE support. It's also packaged for Debian and CentOS now. Write a systemd unit file for your golang service, put Caddy in front of it and you are good to go. It's not a PaaS, but it's simple and shouldn't be too difficult to maintain.