Offline-first architecture
Offline-first sync engine
A PWA sync engine that lets operations teams capture data reliably without connectivity, using background sync, request queuing and conflict resolution.
- Role
- Senior Frontend Engineer, frontend architecture owner
- Company
- AirFi.aero
- Timeline
- 2024–2026
- Stack
- PWA, Background sync, Request queuing, Conflict resolution
Contents
Overview
At AirFi I owned frontend architecture for global airline platforms. One of those platforms served operations teams who often work without a reliable connection, so I architected an offline-first PWA sync engine for them.
Problem
My role
- Architected the offline-first sync engine as part of owning frontend architecture for the platform.
- Set the code-quality, review and delivery standards the frontend team adopted.
Architecture
The engine combines three mechanisms: requests are queued locally while offline, background sync sends them when a connection returns, and conflict resolution reconciles changes made on both sides.
Offline capture, simplified
- Capture dataWorks without connectivity
- Queue requestStored on the device
- Background sync (highlighted)Sent when back online
- Resolve conflicts
Technology choices
- PWA
- Installable web app that keeps working offline.
- Background sync
- Sends queued requests once connectivity returns.
- Request queuing
- Keeps every change made offline until it can be sent.
- Conflict resolution
- Reconciles changes made on the device and on the server.