Samoilenko Yaroslav — Full stack developer

Expertise in Full Stack Web (2.5 yr.), Blockchain and Cryptography (2.5 yr.).

Last verified on April, 2026

Core Skills

PostgreSQL

2 yr.

Bio Summary

Blockchain integration across EVM and Solana networks, including real-time token swaps, wallet management, and secure transaction processing.
Proficient in designing optimized PostgreSQL schemas and implementing microservices with asynchronous processing for high-throughput financial systems.
Master’s degree in Computer Science underpinning solid engineering principles, API design, and agile delivery within cross-functional international teams.

Technical Skills

JavaScript Libraries and Tools	Ethers.js, p5.js, Web3.js
JavaScript Frameworks	Ext JS, Node.js, React
.NET Platform	Identity Server
AI & Machine Learning	Tokenization
Databases & Management Systems / ORM	MongoDB, MS SQL Server Management Studio, PostgreSQL
UI Frameworks, Libraries, and Browsers	CSS3, HTML5, Tailwind CSS
Methodologies, Paradigms and Patterns	Agile, microservices architecture
SDK / API and Integrations	API, Stripe
QA, Test Automation, Security	Code Review
BlockChain and Decentralized Software	Ethers.js, EVM, Optimism, Smart Contract, Solana
UI/UX/Wireframing	Figma
Mail / Network Protocols / Data transfer	WebRTC

Work Experience

Full-Stack Developer - AGNT.HUB (Browser Extension for Social Platforms and Blockchain Financial Services)

Duration: December 2024 – March 2026
Summary:

Developed a browser extension that integrates social media platforms with blockchain financial services, enabling users to perform token swaps and transfers seamlessly within their social feeds
The project aimed to simplify access to decentralized finance by embedding financial operations directly into social interactions

Responsibilities:

Architected and implemented the full-stack solution including frontend, backend, and database layers.
Built a payment processing engine handling real-time token swaps across EVM and Solana networks with transaction validation and error recovery.
Integrated Privy authentication system for secure wallet connections and session management.
Developed an admin dashboard for real-time monitoring, transaction analytics, and operational metrics.
Created a gamified user onboarding system to increase activation rates through progressive feature unlocking.

Technologies: React, TypeScript, NestJS, PostgreSQL, Privy authentication, EVM, Solana

Full-Stack Developer - COWCHAIN (Full-Stack Web3 Applications for DeFi, NFT, and Payment Sectors)

Duration: April 2024 – December 2024
Summary:

Developed full-stack Web3 applications for international clients focusing on decentralized finance (DeFi), non-fungible tokens (NFT), and payment solutions
The projects involved integrating blockchain smart contracts with user-friendly frontend interfaces and backend services to support transaction processing and data consistency

Responsibilities:

Built transaction processing systems integrating smart contracts with frontend interfaces.
Implemented payment flows including wallet connection, transaction signing, gas estimation, and confirmation handling.
Developed backend APIs using Node.js and Express.js for blockchain data indexing and caching.
Modernized legacy React codebase by migrating from JavaScript to TypeScript to improve type safety.
Integrated third-party services such as payment processors, KYC providers, and analytics platforms.
Conducted code reviews focusing on security best practices for financial applications.
Established technical standards for component architecture, state management, and API design.

Technologies: React, TypeScript, JavaScript, Node.js, Express.js, Web3.js, Ethers.js

Education

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

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