Thanks!

> but in Sqlite doesn't WAL mode give you a kind of super simple, super basic temporal data system

Yes-ish.

For one, it is unitemporal. For another, it is for SQLites own transactions, not of the individual datums. Litestream is the way to replicate WAL into an object store / elsewhere. litestream-vfs is also looking good!

https://litestream.io/ , https://litestream.io/reference/vfs/ (announced here: https://fly.io/blog/litestream-vfs/ )

I'm trying to emulate the data assert/redact properties of append-only bitemporal-by-design data stores like XTDB. The giant blog post builds up the intuition from scratch. Or at least tries to.

So my system is going to be: bitemporal data, enforced by SQLite schema and application checks, along with WAL replication for point-in-time transaction backup/restore. Both are entirely distinct, and unaware of each other.