Hi folks,
This is the first place I’ve mentioned this:
We’ve just released a brand new forum platform called Babble.
Everything in front of the application is being handled by Caddy!
All our clients use custom domains. So after initially identifying Caddy as the ideal solution for TLS, we ended up using it for load-balancing, rate-limiting and caching. It’s completely replaced Nginx, and allowed us to simplify our architecture considerably.
One of my goals for this project was to reduce the number of dependencies and moving parts to an absolute minimum, so I’m thrilled with the solution. And yes, shaving down the Caddyfile to the fewest chars possible even lived up to its promise of being “kind of fun” 
Our other app, PlushForums, has been going since 2014. In January 2017 I think we were the first forum platform to ship automated SSL using LetsEncrypt. That was a single-tenant app and a scripted solution just about worked.
That was untenable in a multi-tenant environment, so thank goodness Caddy came on the scene. Big thanks to @matt and the team for a wonderful piece of software that will hopefully allow us and our clients to do great things.
-Adrian
Founder, babble.im