Developer References
The website league communicates through ActivityPub, which is the underlying specification that powers Mastodon and the fediverse. The specifics of this standard are open, published, and come with a test suite for conformance.
Clients to either type of node can be written using the Mastodon API, which both (partially) support. Pillbug, akkoma-fe and friends are all written to the Mastodon API.
Additionally, all Website League nodes require Allowlist Support . This is a non-standardized feature of some nodes that allow those nodes to reject messages not part of the allowlist. this is how we keep the League separate from the wider fediverse, and enforce our standards of conduct (nodes not enforcing them are removed from the allowlist).
Akkoma achieves this through their Message Rewrite Facility, an intentionally flexible mechanism for handling the routing of messages.