Alysanne notesNotes on backend systems, telemetry, distributed data, and the work of Héctor Banderas.https://alysanne.dev/2026-07-21T00:00:00.000ZHéctor BanderasGPS can lie: designing telemetry validation before side effectshttps://alysanne.dev/notes/gps-can-lie/2026-07-21T00:00:00.000ZA practical ordering for duplicate, time, coordinate, rate, and movement checks in an ingestion pipeline.Publishing a multi-tenant ETS index without partial statehttps://alysanne.dev/notes/ets-without-partial-state/2026-07-20T00:00:00.000ZHow composite keys, one mutation owner, and generation swaps turn a fast cache into a dependable read model.Debugging distributed data from the outside inhttps://alysanne.dev/notes/outside-in-debugging/2026-07-19T00:00:00.000ZWhy I begin with the raw request and persisted state, then move inward toward logs and code.