An http server to which one or more domains can be pointed to.
Incoming requests will be proxied to an arbitrary target http server, like Amazon S3, Blogger.com or one of the many options available at sdf.org.
The main idea is to have a server which requires no configuration, handles TLS and can run on mostly any host on the internet with an IP address in one's possession.
Obviously this solution is an end in itself and there already is [Caddy](https://caddyserver.com/).
Thanks to [golang.org/x/crypto/acme/autocert](https://pkg.go.dev/golang.org/x/crypto/acme/autocert), the server will automatically attempt to get a certificate from Let's Encrypt via the [HTTP-01 challenge](https://letsencrypt.org/docs/challenge-types/#http-01-challenge) to enable TLS.