RPOMS Print Engine
Offline-first label printing workstation for the RPOMS refurbishment line
Offline-first browser workstation that drives a thermal Bluetooth printer with zero server latency on the production line.
A TypeScript and React Progressive Web App that turns any PC with Chrome and Bluetooth into a label station for a NIIMBOT B1 Pro. A USB scanner reads a router serial, a prefix-and-length rule names the model, a fixed 50 by 30 mm template is rendered to the printer's raster and printed over one persistent Web Bluetooth session. The print path never touches the network, the app boots offline from cache and IndexedDB, and an optional backend adds Google sign-in, device provisioning and sync. 170 automated tests; one verified print session on the real printer.
Hardware Protocol Driver, Canvas 2D Renderer, Offline PWA & Backend
Key Highlights & Practical Impact
Executive Scan- Eliminated manual phone apps and spreadsheets with a single-scan-to-print browser workstation
- Deterministic model identification from barcode serial prefix and length without network calls
- Offline-by-construction PWA architecture booting and printing from service worker and IndexedDB
- Continuous Web Bluetooth session management eliminating paper rewind and feed jitter between labels
- Canvas-first template editor with automated raster hash freezing to guarantee physical label alignment
- Rigorous verification: 170 automated tests with a simulated printer and headless Chrome validation
Ready to explore the build?
A detailed look at the end-to-end architecture, process workflows, key engineering decisions, live production capabilities, challenges, and results.