Backend engineer · Cryptography · Telegram ecosystem · Financial systems

▸ Telegram bots & Mini Apps — multi-role systems (admin / support / users), moderation, automation
▸ Full-stack TMA platforms — React frontends with Fastify/Node backends, Prisma ORM, Redis queues
▸ Investment platforms — deposits, withdrawals, referral trees, profit distribution
▸ Payment integrations — USDT TRC20, TON, BTC, Altyn card gateway, on-chain tx verification, hidden fee models
▸ Provably Fair gaming — SHA-256 commitment schemes, client-side verification, cryptographic ticket generation
▸ Auth systems — Telegram initData validation (HMAC-SHA256), JWT, custom verification flows
▸ Real-time infrastructure — SSE fan-out, BullMQ async queues, Redis pub/sub, WebSocket-free live feeds
▸ Microservice architectures — separated services for payments, users, analytics, notifications
▸ Async optimization — SQLite/PostgreSQL under load, eliminating DB locks, connection pooling

▸ ЛяБуду — Telegram Mini App lottery platform
    React + Framer Motion · Fastify + Prisma + PostgreSQL + Redis
    Provably Fair (SHA-256) · Multi-game (Lottery ×222, Slots, Wheel, Blackjack)
    Payment system: USDT TRC20 · TON · Card via Altyn · Hidden fee model
    BullMQ payout queue · SSE live feed · Referral engine · i18n (RU/EN)

▸ Crypto Wallet — self-custodial multi-chain wallet
    React + TypeScript · Node.js backend
    USDT TRC20 · TON · BTC · on-chain tx verification
    Key derivation · address generation · balance tracking · transfer flow

▸ Scalable Telegram financial system
▸ Referral engine — multi-level logic, on-chain bonus distribution
▸ Async architecture without locks under DB load

Frontend  │ React 18 · TypeScript · Vite · Tailwind · Framer Motion · Zustand
Backend   │ Node.js · Fastify · Prisma ORM · BullMQ · ioredis
Database  │ PostgreSQL · Redis · SQLite (high-load async)
Crypto    │ USDT TRC20 (TronScan) · TON (TonCenter) · BTC (BlockCypher)
Payments  │ Altyn merchant API · HMAC-SHA256 signing · Webhook verification
Infra     │ Docker Compose · nginx (reverse proxy + SSE) · Telegram Webhooks
Security  │ Provably Fair · JWT RS256 · initData HMAC · Rate limiting

fxranxklin@proton.me · mention From GitHub