Product architecture
How GuardPath keeps every child safe.
An end-to-end view of the device, network, engine and notification layers — built for sub-second elopement detection.
Core data flow
Device → Gateway
GuardTag emits GPS + cellular + BLE pings every 10s over Eview EV-04 protocol.
Traccar normalizes
Self-hosted Traccar gateway translates raw packets into typed JSON events.
Geofence engine
PostGIS computes ST_Contains() against every active zone in under 30ms.
Alert pipeline
Rules engine fires push (OneSignal), SMS (Twilio), and in-app via Ably realtime.
Caregiver app
Alert reaches caregiver in under 8 seconds 99% of the time.
Rules engine
WHEN
Child exits any active zone
THEN
Critical elopement alert · push + SMS in <8s
WHEN
Device battery < 20%
THEN
Warning to caregiver · suggest charge
WHEN
Caregiver in Proximity Mode & child > radius
THEN
Wander alert with bearing & distance
WHEN
School hours + Teacher Mode active
THEN
Two-way voice disabled; parent override available
WHEN
Device offline > 5 minutes
THEN
Caregiver notified, last-known location surfaced
Tech stack
Mobile
React Native · Expo
Web
Next.js 15
API
Node · Fastify
DB
Postgres + PostGIS
Realtime
Ably
Voice
Twilio Programmable Voice
Push
OneSignal
Auth
Clerk
Payments
Stripe + Shopify
Maps
Mapbox + Google
Analytics
PostHog
Infra
Railway · Vercel · Fly.io
Indoor positioning
WiFi + BLE trilateration
When GPS degrades inside buildings, GuardTag scans nearby WiFi BSSIDs and BLE beacons. Signal strengths are sent to our positioning service which trilaterates to ~3m accuracy against a crowdsourced beacon graph.
3m
Indoor accuracy
10s
Update rate
99.6%
Coverage
Compliance & trust
COPPA
Child data minimization, parental consent flow
PIPEDA
Canadian residency option for caregiver data
At-rest encryption
AES-256 + key rotation every 90 days
Annual pen-test
External audit + automated nightly scans