johnnychain
Senior Full Stack Engineer
Senior Full Stack Engineer with 6+ years of experience building scalable web apps across healthcare, eCommerce, marketplaces, and Web3 products. Strong expertise in React.js, Next.js, TypeScript, Node.js, PostgreSQL, GraphQL, REST APIs, and modern web architecture. Experienced in developing crypto payment systems, launchpads, NFT platforms, customer-facing applications, secure integrations, and real-time features. Actively using AI-assisted development tools including Claude, ChatGPT, and GitHub Copilot.
Experience: 6 years
Yearly salary: $80,000
Hourly rate: $40
Nationality: 🇺🇦 Ukraine
Residency: 🇵🇱 Poland
Experience
Senior FullStack Engineer
Five Systems 2024 - 2026
Senior FullStack Engineer for a healthcare platform that enables patients to schedule appointments with healthcare providers online, manage bookings, and communication between patients and medical organizations.
Senior FullStack Engineer
Maven 2022 - 2024
Senior FullStack Engineer for a cryptocurrency payment platform enabling wallet-based transactions across multiple blockchain networks.
Frontend Developer
Trembit 2020 - 2022
Frontend Developer for a large-scale US-based online learning platform serving thousands of users through customer-facing educational products and internal administration systems.
Skills
aws
graphql
javascript
mongo
nestjs
nextjs
node
nosql
postgres
react
solidity
sql
typescript
web3
web3js
full-stack
english
russian
ukrainian