Sqlite3 WebAssembly

Something that would be really fun would be to run SQLite in-memory in a browser but use the same tricks as Litestream and Cloudflare Durable Objects (https://simonwillison.net/2024/Oct/13/zero-latency-sqlite-st...) to stream a copy of the WAL log to a server (maybe over a WebSocket, though intermittent fetch() POST would work too).

Then on subsequent visits use that server-side data to rehydrate the client-side database.

From https://sqlite.org/forum/info/50a4bfdb294333eec1ba4749661934... is looks like WAL mode is excluded from the default SQLite WASM build so you would have to go custom with that.

hi simon. i direct messaged you on twitter about a PoC i did of this in aug 2022, but never heard back - i thought you might have been interested. my twitter handle is justjs14.

i have some code i would have to dig out that did this very thing - it allows you to open a SQLite db in browser using sqlite (with a VFS) compiled to wasm (not the official WASM build), make changes and both push and pull WALs to and from a server (or indeed browser to browser would be possible both manually or over WebRTC). it even works with github pages if you give the browser client a github token to work with.

if you are interested, feel free to ping me and i can see if i can get this up and running from scratch again. i did a ton of experiments with this approach around then and i think it could be useful for a subset of applications at least.

there's also a working demo of the pull functionality only here: https://just.billywhizz.io/sqlite/demo/#https://just.billywh...