Field-service enterprises, aviation/maritime operations, point-of-sale (POS) terminals, and healthcare teams operating in spotty Wi-Fi environments frequently search to hire a freelance offline-first Progressive Web App (PWA), Service Worker & IndexedDB sync programmer. I am Aldian Fazrihady, a Senior Freelance Full Stack Developer available via Upwork.
Core Offline-First Web & Local-First Sync Capabilities
- Workbox Service Workers & Deterministic Asset Precaching: Engineering installable PWAs with instant offline boot, background sync queues (`BackgroundSyncPlugin`), and Web Push Notifications.
- Local-First IndexedDB / OPFS SQLite Engines: Storing tens of thousands of relational records locally in the browser using Dexie.js, RxDB, PowerSync, ElectricSQL, or WebAssembly SQLite (`wa-sqlite` / OPFS) for sub-millisecond local reads and writes.
- Conflict-Free Delta Synchronization: Resolving offline multi-device edits gracefully when connectivity returns using per-field Hybrid Logical Clocks (HLC) or CRDTs.
Frequently Asked Questions
How do you prevent "Draft saved" badges from misleading users before data is actually persisted?
I separate local IndexedDB persistence indicators from server-sync confirmation states, ensuring save indicators only trigger after active user edits are durably committed—never on initial component mount or hydration.
How can we hire you as a freelance Offline-First PWA programmer?
Reach out on Upwork.