oh I think peritext is "automerge" with formatting? which is referenced by OP. OP calls it a "json-based CRDT", which is true for automerge, but that description may be confusing: JSON is the "storage/(transport?) datastructure", the "materialized datastructure" for automerge is plain text. Note that one of the creators of peritext (martin kleppmann) is also creator of automerge.