Prelude: Why I didn't want to use serde-json Last week, I was looking into exploring ActivityPub, the protocol that powers Mastodon and the Fediverse. It uses a standard format for its JSON payloads: JSON-LD Compacted Document Form. A simple ActivityPub activity could look like this: { "@context": "https://www.w3.org/ns/activitystreams", "type": "Note", "to": ["https://chatty.example/ben/"], "attr