Cloudflare has an api for easy dynamic dns. I use oznu/docker-cloudflare-ddns to manage this, it’s super lightweight:

docker run \
  -e API_KEY=xxxxxxx \
  -e ZONE=example.com \
  -e SUBDOMAIN=subdomain \
  oznu/cloudflare-ddns

Then I just set CNAMEs for my public facing services to point to ‘subdomain.example.com’ and a reverse proxy to get incoming traffic to the right service.