It is posted once in 2020. But there is an update:
Glitch launched the Static Site in 2020:
It has recently been updated to allow you to go to a static site after a build:
https://help.glitch.com/kb/article/113-i-noticed-a-“glitch”-entry-in-the-react-and-eleventy-starter-projects’-package-json-what-does-that-do/
This has increased the benefits of using Caddy with Glitch.
That’s why I recently added some projects (PoC).
Caddy v2 Proof of Concept
https://glitch.com/edit/#!/caddyv2
It’s a previously published project (PoC), but with the GENERATED STATIC SITE attribute.
It builds less and consumes less of your Project Hours.
For example, you can output a custom 404 page. This has been requested by the Glitch Forum for some time. Caddy can do this!
Redirect Proof of Concept
https://glitch.com/edit/#!/redirectpoc
A redirect is achieved using Caddy’s redir.
You can 301 redirect from your Glitch project to another server or web service.
With the GENERATED STATIC SITE attribute, you can use other Glitch projects.
Caddy Proof of Concept (simpler)
https://glitch.com/edit/#!/caddypoc
For those who are accustomed to using Caddy. 
You could publish a more interesting project (PoC). 
Other projects (PoCs)
This previously published project is still valid:
https://glitch.com/edit/#!/caddy-v1 - Caddy v1 (With GENERATED STATIC SITE attribute)
Also, I knew webinstall.dev and webi, so I adopted it.
Caddy 2.4.0 has just been released, but I could easily update it. 
Of course you can also install the Caddy binaries directly instead.
Enjoy! 
