i think activityPub stands on the shoulders of giants as there was a solid decade+ of web ontology development that was basically abandoned around 2012-14 because the tech oligarchs didn't think it was going anywhere, the only people interested in semantics n such in the 2010's were indie web people
i didn't know parsing json-ld was a hassle in other languages, i'm sorry to keep shilling php here but there's this built in function
json_decode() you just take a json file or string and it turns it into an array, so you just work with an array, and if you want to turn it into json again you do json_encode and that's that, like the whole backend of this forum i'm working on is just folders with json files in it until i get the sql tables figured out, even then i kinda like the flatfile json idea Eventually what I'm working on should serve as a basis of a minimal fedi instance, i've been playing around with a bunch of old fedi backups, the weird thing i've noticed is that mastodon, pleroma/akkoma and *key variants format their fedi backups slightly differently, like the way mastodon does it is highly redundant ( the more I learn about the technical stuff, the more i hate mastodon and it's consequences )
but i'm not even gonna fuck with activitypub directly, gonna use this library which handles most of that ( landrok.github.io/activitypub/ ) and i'm basically gonna just rip off the Misskey Sql tables lol