Helmet.

Helmet is a Saudi marketplace where customers book on location car washes and bikers execute the jobs in the field. I built the Express and MongoDB API plus the React admin dashboard that power the customer and biker mobile apps: geo service zones, hard per biker calendars, admin walk in bookings with Moyasar invoice links, wallet and subscriptions, and realtime operations.

1. 01Designed the hard scheduling system with per biker calendar ranges, vacations, wash duration slot stepping, and consecutive multi car booking blocks
2. 02Built geo based availability so customers get free slots from bikers assigned to their service area
3. 03Implemented Moyasar payments for app checkout and shareable e invoices for admin walk in bookings, plus tax ready invoice payloads
4. 04Modeled the booking lifecycle from pending payment through on way, arrived, washing, and completed, with photo evidence gates for bikers
5. 05Delivered the admin dashboard with Command Center, bookings, schedules, workers, map zones, catalog, promos, complaints, and commissions
6. 06Added wallet credits, VAT, promo codes, subscriptions, gifts, tips, refunds, Socket.IO live updates, and FCM push

• Customer and biker mobile apps consume this API
• Admin dashboard and backend are the surfaces I owned end to end