Officer-safety platform for a state law-enforcement agency

A state law-enforcement agency needed an officer-safety platform across iOS and Android: duress alerts, fall detection, welfare check-ins, Bluetooth push-to-talk integration with a third-party hardware button, and reliable forwarding to an existing dispatch system.

The hard parts were not the features. The hard parts were the non-functional realities: iOS aggressively kills background processes; the duress hardware uses a custom BLE GATT service that needs persistent connection; an officer in distress is exactly the time when connectivity is least reliable. Existing solutions either didn't survive backgrounding, didn't handle the duress hardware, or coupled the mobile clients so tightly to a specific backend that swap-out was impossible.

A three-tier architecture, native everywhere it mattered, and engineered for the failure modes specifically.

On iOS, native Swift/SwiftUI with ActivityKit Live Activities for visible in-progress duress states, the Apple Location Push Service Extension for genuine background location updates (silent push is rate-limited and unreliable for safety-critical work), and a durable on-device outbox so a duress alert begun on the platform survives the connectivity dropping mid-send. App Groups and Keychain coordinate state between the main app and the location-push extension.

On Android, native Kotlin and Jetpack Compose with a foreground location service, Hilt for dependency injection, Room for local persistence, and WorkManager for retryable delivery work. The same on-device outbox discipline as iOS.

The middleware relay is framework-free Go — net/http only, no web framework footprint. JWT authentication, SQLite WAL persistence, end-to-end APNS push pipeline, an embedded go:embed admin SPA so the operator-side tooling ships in the same binary as the relay. HTTPS forwarding to the upstream dispatch platform.

The whole lineup is gated by an independent black-box UAT suite — Bun, Cucumber, and Maestro for mobile flows — with @spec trace comments linking each test back to its SRS clause. CI release gates are spec-traced, not subjective.

Production deployment in the agency's environment. Multi-thousand-device fleet under live operations. Spec-traced UAT suite gates every release. Mean time to duress-alert acknowledgement is measured against an operational target, not against best-effort.