I struggled with this landscape a few years ago when building Mere Medical to manage my own medical records. To be fair, I was aiming for not just offline-first, but offline-only (user data was exclusively stored on device, not in any server). I got surprisingly far with RxDB, but it definitely felt like I was pushing these tools and the web platform to their limit.

There’s just an assumption that these client databases don’t need mature tools and migration strategies as “it’s just a web client, you can always just re-sync with a server”. Few client db felt mature enough to warrant building my entire app on as they’re not the easiet to migrate off of.

I also tried LokiJS which is mentioned in the OP. I even forked (renamed it SylvieJS lol) it to rewrite it in TS and update some of the adapters. I ultimately moved away from it as well. I found an in memory db will struggle past a few hundred mbs which I hit pretty quickly.

No matter what db you use, you’re realistically using indexed db behind the hood. What surprised me was that a query to indexed db can be slower than a network call. Like what.

On midrange and below Android devices, literally any local persisted data access can be slower than a network call. Even a point read from a small SQLite b-tree can be coming off a $3 microsd card and a CPU equivalent to a 10 year old iPhone. https://infrequently.org/2024/01/performance-inequality-gap-...