It was not immediately obvious to me on how to setup Caddy as a proxy to Github Pages, this was mostly due to a misunderstanding on how Github Pages work, but thought I’d share a quick guide to hopefully clear up any questions.

Configuring Github Pages

I won’t go into much detail here, a good guide to get started is located here. What’s important is to remember what you set your Custom domain as. This will be the site you need to serve via Caddy. In this example my Custom domain is set as tears.io.

Configure Caddy

tears.io {
    header / {
        # Enable HTTP Strict Transport Security (HSTS) to force clients to always connect via HTTPS
        Strict-Transport-Security "max-age=31536000;"
        # Enable cross-site filter (XSS) and tell browser to block detected attacks
        X-XSS-Protection "1; mode=block"
        # Prevent some browsers from MIME-sniffing a response away from the declared Content-Type
        X-Content-Type-Options "nosniff"
        # Disallow the site to be rendered within a frame (clickjacking protection)
        X-Frame-Options "DENY"
    }
    proxy / http://sunshinekitty.github.io/ {
        transparent
    }
    log /var/log/caddy/tears.io-access.log
    errors /var/log/caddy/tears.io-errors.log
    gzip
}

The transparent setting in the proxy directive is short-hand for:

header_upstream Host {host}
header_upstream X-Real-IP {remote}
header_upstream X-Forwarded-For {remote}
header_upstream X-Forwarded-Proto {scheme}

Note that the proxy directive is pointing to my main Github Pages page, and not to the sub-page of /tears.io. This is on purpose, Github Pages knows to serve the normal site as long as the Host header is set to tears.io in this instance.

That wraps things up, this shows how this blog is hosted from Github Pages at github.com/sunshinekitty/tears.io.

Addendum: Now in 2019 I am hosting my website from Gitlab pages with Cloudflare providing SSL. I will stick with this for the time being, if Gitlab does something to betray my trust I could see moving to something like GCS and Cloud Builder in GCP.