Ярослав

SAMOILENKO YAROSLAV
Full stack developer
[открыть контакты](см. выше в блоке «контактная информация») | LinkedIn | Telegram | Kharkiv
SUMMARY
Full-stack developer with 2+ years of product experience building applications from concept to scale, backed by a
Master's degree in Computer Science. My core expertise lies in React/TypeScript frontend development, paired with
strong backend skills in Node.js and NestJS for building robust APIs and data processing pipelines. I am experienced in
modernizing legacy codebases while maintaining production stability, and I thrive in fast-paced, autonomous
environments where rapid iteration and business impact drive decisions.

WORK EXPERIENCE
Full-Stack Developer, AGNT.HUB December 2024 – March 2026
Architecting and implementing browser extension that bridges social platforms with blockchain financial services,
enabling 10,000+ users to execute token swaps and transfers without leaving their feed
Building production payment processing engine handling real-time token swaps across EVM and Solana networks
with transaction validation and error recovery logic
Designing and implementing full-stack architecture: React/TypeScript frontend, NestJS backend APIs, PostgreSQL
database with optimized schema for financial data
Integrating Privy authentication system providing secure wallet connections and session management for financial
operations
Developing admin dashboard for real-time platform monitoring, transaction analytics, and operational metrics
tracking
Creating gamified user onboarding system increasing activation rates through progressive feature unlocking
Full-Stack Developer, COWCHAIN April 2024 – December 2024
Developing full-stack Web3 applications for international clients across DeFi, NFT, and payment sectors
Building transaction processing systems integrating smart contracts with frontend interfaces, ensuring data
consistency between blockchain state and application database
Implementing payment flows including wallet connection, transaction signing, gas estimation, and confirmation
handling
Developing backend APIs using Node.js and Express.js for blockchain data indexing, caching frequently accessed
on-chain data to reduce latency
Modernizing legacy React codebase by migrating from JavaScript to TypeScript, improving type safety and reducing
runtime errors by 40%
Integrating third-party services including payment processors, KYC providers, and analytics platforms
Conducting code reviews focusing on security best practices for financial applications
Establishing technical standards for component architecture, state management, and API design across
development team

EDUCATION
Master's Degree, Computer Science Sep 2012 - May 2018
Ukrainian State Engineering Pedagogical Academy

KEY SKILLS
Frontend Development
React, Next.js, TypeScript, JavaScript (ES6+), HTML5, CSS3, Tailwind CSS, Component Architecture, Responsive Design
Backend Development
Node.js, NestJS, Express.js, RESTful APIs, Microservices Patterns, Asynchronous Processing, Database Design,
PostgreSQL, MongoDB, SQL Optimization, Database Schema Design, Data Migrations
Financial Systems & Blockchain
Payment Gateway Integration, Transaction Processing & Validation, Wallet Management, Token Economics, Smart
Contract Integration (EVM, Solana), Web3.js, Ethers.js, On-chain Data Processing
Design & Product
Figma, User Flow Design, Pixel-Perfect Implementation, Product Thinking
Collaboration & Process
Cross-Functional Team Leadership, Technical Documentation, Code Review, Agile Delivery, Stakeholder Communication
Spoken Languages
Ukrainian (Native), English (B1+ - working daily with international teams)