While trying to sign in to pixelfed.social using my own site’s domain on their Sign-in with Mastodon feature, I received the following message from pixelfed: „This server is not compatible, please choose another or try again later!“
When I researched the reason for this behaviour, I found out:
- pixelfed uses FediDB as its sole arbiter to decide whether a site is capable of acting as its login server.
- FediDB is run by Daniel Supernault, pixelfed’s prevailing contributor.
- Sites are registered in the FediDB when their crawler finds that…
- …they adhere to the NodeInfo protocol which requires the presence of a JSON LD resource in /.well-known/nodeinfo pointing to a secondary resource that serves the schema document built according to one of the NodeInfo schemas.
- …they contain an
/api/v1/instanceresource. The expected content of this resource is not specified. This is a resource found on Mastodon servers.
In other news, it’s worth noting that transferring your content between two Pixelfed instances is currently not possible. This situation brings to mind Robert’s Law: „If you host your content elsewhere, you will lose it in the end.“