Developer
Specialised in building marketplace platforms end-to-end: four coordinated applications (customer, courier, restaurant, operations) over one zero-dependency Node.js backend with realtime order flow, live GPS tracking on a hand-built map engine, gateway-ready payments, and a fully mirrored Arabic-first / French interface — shipped from empty folder to a TLS production VPS.
Technologies engineered
A deliberately lean, self-contained stack — no frameworks, no build step, nothing the author didn't write or fully control.
Challenges overcome
The problems that separate a template from a platform — each solved, verified live, and in production.
Four apps, one heartbeat
An order is touched by three humans and one clock: the kitchen accepts, the courier delivers, the admin overrides — and untouched demo orders must still advance on their own. Engineered a single state machine with actor precedence: kitchen acceptance freezes the auto-clock, courier actions take over the delivery leg, admin override wins over everything, and every transition fans out instantly to the other three surfaces.
Realtime without the weight
WebSocket libraries were off-budget by principle (zero dependencies). Chose Server-Sent Events over a bare Node HTTP server: per-role subscription filtering, keep-alive pings, and a 15-second polling safety net. Deployment gotcha solved: nginx silently buffers event streams, so the proxy config disables buffering on the events route. Measured order-to-notification latency: ~4 ms.
A map engine from scratch
No Leaflet, no Mapbox. Wrote a ~200-line Web Mercator engine — OSM tile lifecycle with caching, pointer-drag panning, zoom clamping, marker anchoring, SVG polylines — powering four different maps: customer live tracking, a drag-to-pin delivery address picker, the courier's night-mode course map, and the admin's live fleet view.
GPS that demos itself
Couriers stream real browser geolocation to the server, which relays each fix to the right customer's map over SSE. But a desktop demo has no GPS — so a movement simulator walks the courier from restaurant to doorstep and yields the floor automatically the moment a real fix arrives (12-second freshness window). Live dot on the customer's map, either way.
Fairness as architecture, not marketing
The platform's differentiator is a courier fairness charter — enforced in code: net gain computed server-side from real haversine kilometres before acceptance, commission capped at 12%, customer tips forwarded 100% with double-credit guards, and refusing an offer writes nothing negative anywhere. The charter is an API contract, not a slogan.
Arabic-first, mirrored to the pixel
Most delivery platforms bolt Arabic on last. GoBro is RTL-native: one dictionary drives Arabic and French across all four apps, layouts mirror through CSS logical properties, Tunisian dinar renders with millimes and Western digits, and maps deliberately stay physical while the UI flips around them.
A full rebrand with zero regressions
Mid-project, the owner delivered a new visual identity (black × amber, navigation-arrow logomark). Because every surface reads from one OKLCH token system and the logo is a single generated SVG component, the entire five-surface replatform was reskinned — favicons, PWA manifest, dark mode included — with zero functional diffs, verified by an end-to-end pass.