01
Reconciled to the cent
Money systems get double-entry thinking whether they asked for it or not: balances derivable from history, idempotent movement, no state that can half-happen. A retried job must never spend twice.
Reza Heydari · Full-Stack TypeScript Engineer · Remote · Worldwide
Marketplaces.Booking systems.Payment infrastructure.
I'm Reza — six years shipping production platforms end to end: schema to interface to deploy. TypeScript the whole way down, and systems built to stay boring after launch, because several of them move real money.
01The record
- years shipping production platforms
- 6
- products built at one company
- 9+
- running money infrastructure
- 5y
- response time, worldwide
- 24h
02Selected work
01
Crypto wallet & transaction infrastructure
The wallet and transaction system behind a crypto exchange: deposits, withdrawals, txid tracking, and balance reconciliation on TRON — plus the payment infrastructure that powered nine more products around it.
TypeScriptNode.jsTRON APIsMySQL5y 4m
dev to CTO at one exchange
In production
02
Gold exchange platform
A gold-exchange back-end where every order settles against a physical commodity. Type-safe transaction handling end to end, on a deliberately modern runtime — Bun and ElysiaJS in production.
TypeScriptElysiaJSBunPrismaAu
a real commodity, settled
Delivered
03
Therapist booking automation
A Finnish health-tech platform connecting therapists and clients. I set the technical direction and shipped the piece that mattered most: fully automated booking, from an open slot to a Google Meet link, across timezones.
TypeScriptNext.jsNode.jsGoogle Calendar API0
manual steps per booking
Delivered
03How I build
02
Secure by construction
Keys and secrets live outside application code. Inputs are validated at the boundary. Correctness is enforced by database constraints, not by hoping every caller behaves. The boring, unglamorous discipline that keeps systems out of the news.
03
Schema before UI
The data model is the product's skeleton. I design it first, make invalid states unrepresentable where practical, and let the interface grow from a foundation that won't need re-pouring.
04
Boring in production
Docker images, repeatable releases, monitoring, and a rollback path measured in seconds. Excitement belongs in the product, never in the deploy. Six years of Linux servers taught me which one users notice.
04Experience
2026 — now
Full-Stack Engineer · Freelance
Remote · Worldwide
Independent full-stack delivery — dezmenu.ir and sasanzalaghi.ir shipped end to end, from design to production deployment.
ReactNext.jsNode.jsDocker2025 — 2026
Full-Stack Engineer & CTO · Yara Health
Finland · Remote
Technical direction for a health-tech platform; automated therapist booking from open slot to Google Meet link via the Google Calendar API.
TypeScriptNext.jsGoogle Calendar APIPostgreSQL2025
Senior Back-End Developer · TalaAvan / Madar Holding
Part-time
Back-end for a gold-exchange platform trading a real commodity — ElysiaJS and Bun on Docker, transaction handling designed schema-first.
ElysiaJSBunPrismaMySQLDocker2020 — 2025
CTO & Full-Stack Developer · TetherLand
5 yrs 4 mos · four roles
Led all technical decisions while shipping 9+ products. Built the TRON crypto wallet and transaction system — wallets, txids, and balances reconciled to the cent.
TypeScriptReactNode.jsTRON APIsMySQLDocker2021 — 2022
Founder · IRPlayers
Side venture
Responsive gaming platform on React Native Web — web, Android, iOS, and PWA from one codebase.
React Native WebNode.js2019 — 2020
Front-End Developer · Bamadar / Madar Holding
WooCommerce hypermarket application plus Linux deployment — where the end-to-end habit started.
ReactWooCommerceLinux
05Registry
Front-End
- React
- Next.js
- TypeScript
- React Native
- Tailwind CSS
- Motion
Back-End
- Node.js
- Express
- ElysiaJS
- Bun
- REST APIs
Data
- Prisma
- MySQL
- PostgreSQL
- Transaction handling
Infrastructure
- Docker
- Linux servers
- GitHub Actions
- PM2
- nginx
- Git
06Ways to work with me
You need a platform built end to end
Marketplace, booking system, SaaS — from schema design through UI to production deployment, owned by one accountable engineer.
You need payments or wallet infrastructure
Checkout flows, ledgers, crypto rails, reconciliation. Systems where a bug costs money — designed so it can't.
You need a senior TypeScript engineer embedded
Full-time remote or contract, inside your team and your codebase. EU and US overlap, async-first, English or Persian.
You need an existing system rescued
Audit, stabilize, refactor. I've inherited enough production systems to respect the ones that work and fix the ones that don't.
International clients: invoicing with bank transfer (CHF · EUR · USD · GBP) or PayPal. Replies within 24 hours — Telegram is fastest.
07Contact
Building something that has to hold?
Available now for full-time remote roles and serious project work. Replies within 24 hours — Telegram is fastest.
- Emailreza.apada@gmail.com
- Telegram@apadaa — fastest
- LinkedInin/reza-heydarie
- GitHubapada-appleid
- Phone+44 7383 378386
Remote · Worldwide · EU & US overlap · English / Persian
