Hi Dale, I'm one of the local-first paper coauthors. I'm a fan of PouchDB (thanks for that) and the whole CouchDB lineage--the CouchDB book[1] was an early inspiration in my exploration of next-gen storage and collab models.
I've been down the CouchDB/PouchDB path several times with several different engineering teams. Every time we were hopeful and every time we just couldn't get it to work.
As one example, I worked with a small team of engineers to implement CouchDB syncing for the Clue Android and iOS mobile apps a few years back. Some of my experience is written down here[2]. After investing many months of engineering time, including some onsite help from Jan Lehnardt[3] we abandoned this architecture and went with a classic HTTPS/REST API.
Other times and with different teams we've tried variations of Couch including PouchDB with web stack technology including Electron and PWA-ish HTML apps. None of these panned out either. Wish I could give better insights on why--we just can't get it to be reliable, or fast, or find a good way to share data between two users (the collaboration thing is kind of the whole point).
I'm currently working on an app using PouchDB, and the approach I've taken is using one database per "project" in my app. I'm not there yet, but I'll use another database to manage users & access control. These aren't things you want to sync anyway; I might even end up with a regular SQL database for this (I haven't decided yet).
I hope this approach avoids most of the pitfalls you mentioned.
Your Git analogy is also spot-on, but I think you don't take it far enough. Creating a repo is cheap, and I believe CouchDB databases are, too (altough I'm still very new at this). You seemed hesitant to create too many.
Good point about notifications, though. I think you'll still have to have a server process that manages that kind of thing (and probably inserts notifications in other users's databases).
I've been down the CouchDB/PouchDB path several times with several different engineering teams. Every time we were hopeful and every time we just couldn't get it to work.
As one example, I worked with a small team of engineers to implement CouchDB syncing for the Clue Android and iOS mobile apps a few years back. Some of my experience is written down here[2]. After investing many months of engineering time, including some onsite help from Jan Lehnardt[3] we abandoned this architecture and went with a classic HTTPS/REST API.
Other times and with different teams we've tried variations of Couch including PouchDB with web stack technology including Electron and PWA-ish HTML apps. None of these panned out either. Wish I could give better insights on why--we just can't get it to be reliable, or fast, or find a good way to share data between two users (the collaboration thing is kind of the whole point).
[1]: https://guide.couchdb.org/
[2]: https://medium.com/wandering-cto/mobile-syncing-with-couchba...
[3]: https://neighbourhood.ie/couchdb-support/