Context
Late, duplicate, or out-of-order GPS must not rewrite the operational past. Geospatial automation looks like a map. It is a problem of time.
Atlas Dispatch is a synthetic fleet lab for that invariant.
Decision
PostgreSQL/PostGIS owns scenarios, plans, assignments, commands, telemetry, and audit. Redis holds disposable live state. Telemetry observations are immutable. Duplicate, late, and noisy points still land as receipts. Current location, trails, geofences, and ETA are rebuildable projections.
observation receipt → immutable fact → rebuild live projection
Device commands have durable identities and report stale-plan conflicts instead of overwriting silently. The driver console works offline and replays with idempotency.
What I rejected
Updating “current location” in place, and treating Redis as the historical log. A late point would then erase a fact you can no longer replay.
Failure scenario
A point from minute 12 arrives after minute 14. Both receipts exist. Projections rebuild. The operational past is the observation log, not whatever the map last painted.
Evidence
PostGIS facts, live-state Redis, and tests for late and out-of-order telemetry. There are no real people, vehicles, or locations in this repo.
Inspect: Repository · Run locally