So, short answer, no, not through docker-compose on its own – it’s something I’d like to see, but the plan here is to allow anyone to create a customized base image that can be shared publicly to push the ball forward. Building a plugin involves cloning the plugin, bundle install, npm, and recompiling ember… This should not be done on boot.
So part of the idea here is to allow images to build just as discourse/discourse is – with the same app.yml as the supported Discourse versions are running.
As a sample, I’m building my personal image with resenha by updating the core app.yml to include the plugin here and then pushing it up to an external (public!) docker registry.
If you’re using an external mail service, I don’t think your caddy reverse proxy probably isn’t the problem. Unlike the current launcher builds, discourse/discourse will not nag you about setting up your email env vars (but it’s still necessary to do) – I’d check those first.