I'll be keeping a list of atproto links here. These are resources I check occasionally while implementing dnproto.
PDS implementations
https://github.com/threddyrex/dnproto - my PDS. Implemented in C#.
https://github.com/DavidBuchanan314/millipds - millipds. Implemented in Python. Single-user. I read through this code a bit during the early stages of writing dnproto.
https://tangled.org/hailey.at/cocoon - cocoon. Implemented in Go. Also read through this a bit.
https://github.com/ascorbic/cirrus - cirrus. Runs the Typescript implementation on CF workers.
https://github.com/blacksky-algorithms/rsky - rsky. Implemented in Rust.
https://tangled.org/tranquil.farm/tranquil-pds
https://tangled.org/chadtmiller.com/pds.js
https://tangled.org/futur.blue/pegasus
Docs for building a PDS
https://github.com/bluesky-social/atproto/discussions/2350 - What does a PDS implementation entail?
https://docs.bsky.app/docs/api/at-protocol-xrpc-api - AT Protocol XRPC API
https://docs.bsky.app/docs/advanced-guides/api-directory
https://atproto.com/specs/event-stream
https://atproto.com/specs/repository
https://www.da.vidbuchanan.co.uk/blog/adversarial-pds-migration.html
Data formats
https://dasl.ing/drisl.html - DRISL (was DAG-CBOR)
https://dasl.ing/car.html - Content-Addressable aRchives (CAR)
Self-hosting a PDS
https://github.com/bluesky-social/pds
https://whtwnd.com/bnewbold.net/3l5ii332pf32u
Discussion communities
https://discord.gg/3srmDsHSZJ - AT Proto Touchers Discord. One of the main places where folks chat about atproto.
https://github.com/bluesky-social/atproto/discussions
https://github.com/bluesky-social/pds/discussions
https://discourse.atprotocol.community/c/discussion/4