AuthOS looked like it had a SQLite problem. It really had blocking crypto, noisy writes, audit logs on the hot path, and no load-shedding discipline.
How we migrated our SSO platform's test suite to SQLite, broke it, and fixed it by understanding database locking and connection pooling.
A fast Rust and SQLite auth service is only interesting if it buys you a real product: multi-tenant SSO, OAuth, governance, analytics, and SDKs without renting an identity vendor.
A Rust and SQLite auth service collapsed, recovered, and eventually showed why a well-understood monolith can be economically serious before distributed machinery earns its keep.