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How does one read a protocol specification and write an implementation from scratch?
I'd love to see a Ruby #ActivityPub gem, but I have a very limited understanding of how to build one myself.
@deadsuperhero not easy to explain I'm afraid. Reading a specification can depend on how it's written. But the specification is there to help you. See the difference between message A and message B. It's language if you like. Writing a parser is a lot about filtering out the information in a stream. Picking out the values you are after and classifying them. Once you have that, you can connect actions to those. Thats the theory, but do read some existing implementations for help :)
Good luck!