It does seem mostly possible to host a Docker registry with static files and a bit of config:

https://github.com/jpetazzo/registrish

I haven’t tried running this yet, but it seems worth keeping in mind. It’s relatively simple software so the idea could probably be pretty easily adapted to other situations.

I recall mentioned here ttl.sh, which as I looked it up [0], uses through Docker a CNCF project called Distribution Registry [1] which implements the core container registry functions (and appears to have additional utility, like being a pull-through cache).

0. https://github.com/replicatedhq/ttl.sh/blob/main/registry/en...

1. https://distribution.github.io/distribution/

It's certainly possible with s3, so probably for any other static host https://news.ycombinator.com/item?id=40942732