I build the software that takes the payment — and the apps and websites around it.

Turned our payment terminal into the card reader inside vending machines. The machine asks for a price over the MDB bus; the terminal takes the card and tells the machine whether to release the item.

• Upgraded the MDB library and moved prices to 32-bit, so high-value items charge the right amount.
• Automatic refund when a paid item doesn't drop, or the machine loses power mid-sale.
• Self-healing connection and a clear vending screen, tuned for both a phone-size and a square 480×480 terminal.

A Windows app that pretends to be a vending machine, so a payment terminal can be tested without one. Choose a product, pay on the real terminal, and watch the machine release it — or fail on purpose.

• Scenarios for every outcome: sold out, fridge door open, motor jam, power cut, cancel, decline, timeout.
• A live protocol log that translates every byte on the bus into plain words.
• Built with tools already in Windows, so anyone on the team can run it.

Day-to-day work on the terminal app used by merchants: card flows, receipts, settlement and cash-register links, across several device models and three languages.

• Contact, contactless and magstripe payments with PIN, reversals and currency conversion.
• Fixes found by reading the device's own logs — down to a printer motor that made the card reader see a "swipe".
• Unit-tested business logic, so releases don't break what already works.

A motorbike-taxi and small-parcel delivery app for a Beirut taxi office, built once in Kotlin Multiplatform for Android and iOS. Riders order on a map, drivers accept jobs, and the office manages everything from its own dashboard.

• Three roles in one app: rider, driver and office manager, in Arabic (right-to-left) and English.
• Fares calculated on the server from the office's rules, so they can't be tampered with; cash or card payment.
• Smart dispatch: only free drivers are notified, the first valid accept wins, and the manager can assign a driver or approve each job.
• Live driver tracking, monthly financial reports and commission settlement, on Firebase (Auth, Firestore, Cloud Functions, push).

My own online team shooter for Android, set in real Beirut neighbourhoods (Downtown, the Souks, Hamra, Ain El Mreisseh and Raouche), which are generated in 3D from OpenStreetMap and elevation data.

• A custom 3D engine with OpenGL ES in Kotlin: streets with traffic and people, real landmarks and hills.
• Live multiplayer matches synced over Firebase, with public or password rooms, custom teams and team voice chat over WebRTC.
• 12 real guns, 20 military ranks, first and third person, a global ranking, and your own face on your soldier using the front camera (ML Kit).

Coming soon on Google Play · See the game page

Designed and delivered a merchandising app for field teams from scratch to deployment, owning the whole lifecycle from architecture to customer delivery.

• Offline-first: data syncs reliably between online and offline with no data loss.
• Payment, reporting and analytics SDKs, plus receipt and report printing across printer models.
• Clean MVVM with Strategy, Chain of Responsibility and Repository patterns; mentored juniors and introduced unit tests, CI and peer reviews.