Senior Full-Stack Software Engineer
I turn hard business problems into reliable software.
Website · Portfolio · Blog · LinkedIn
For 16+ years I've designed, built and led production systems for businesses in the US, Australia, Singapore and Europe: payments, bookings, point of sale, marketplaces and SaaS platforms.
I take ownership of the parts a business can't afford to get wrong: money, bookings, supplier data, and the older systems that still hold everything together.
Currently Lead Software Engineer at Gourmeal, leading a team of 4–5 engineers on an in-venue food-ordering platform.
- Bookings and payments. Booking engines and checkouts where the money has to be right every time.
- One product, many suppliers. Many partners' data and rules behind one catalogue and one booking flow.
- Modernizing legacy systems. Replacing aging platforms piece by piece while the business keeps running.
- Leading small teams. Code review, planning, mentoring and hiring for teams of 2–5 engineers.
- Security and compliance. Security reviews, penetration-test fixes and regulatory reporting.
| Business | What I did | Result |
|---|---|---|
| Car-rental comparison and booking (Australia) | Put 10+ rental suppliers behind one booking system, with white-label partner sites | 4M+ rentals across 5 countries |
| Cruise and tour retailer (US) | Designed one catalogue fed automatically by seven tour operators | Tour and search pages several times faster |
| Point of sale for regulated retail (US) | Led the team building sales, delivery, inventory and state compliance reporting | A wholesale product spun off from the platform |
| Consumer and merchant e-wallet (Singapore) | Built money movement and most of the marketplace seller portal | Double-spend risk from a penetration test fixed |
| Legal-tech search for SEC filings (US) | Sole engineer: built the whole subscription product | 100k–1M contract exhibits indexed |
| Gourmeal, food ordering at events (US) | Moved pricing and payments server-side; wrote the first security review | Critical, high and medium findings fixed within three days |
More detail on each project: portfolio.asmshaon.tech
- Business first. Start from the problem and measure the work by what it changes.
- Safe by default. The server decides prices, money moves all-or-nothing, and data is never half-updated.
- Replace, don't rewrite. Move one piece at a time and keep the old path working until the new one is ready.
- Clear and dependable. Plain updates, deadlines kept, and long-term working relationships.
PHP (Laravel, Symfony) · Go · TypeScript (Next.js, React) · MySQL · Redis · AWS · Docker · GitHub Actions · Stripe
Have a problem worth solving? Get in touch