Probably not the ‘recommended’ way, but I use a selfsigned cert for each service I’m running generated dynamically on each run with nginx as a reverse proxy. Then I use HAproxy and DNS SRV records to connect to each of those services. HAproxy uses a wildcard cert for the real domain and uses host mapping for each subdomain.

This way every service has its traffic encrypted between the HAproxy and the actual service, then the traffic is encrypted with a browser valid cert on the frontend. This way I only need to actually manage 1 cert. The HAproxy one. Its worked great for me for a couple of years now.