Just wanted to share how I accomplished this, it was a little easier than I first thought.
From an already running machine, with Caddy acting as a reverse proxy for a number of existing Docker containers already.
- Clone discourse as per the official instructions
- Copy /var/discourse/samples/standalone.yml->/var/discourse/containers/app.yml
- Fill in SMTP settings and website address
- Comment out 443:443from theexpose:section
- Replace 80:80->3001:80, 3001 being the port I’m serving via Caddy
- Run ./launcher rebuild app
- Done
Whop!