Oleksiy S.
Verified expert
Oleksiy S.
Verified expert
Top skills
Meet Oleksiy ✨
A Full Stack Developer with five years of experience building high-complexity, production-grade SaaS platforms where architecture, performance, and reliability are not optional. Oleksiy works at the system structure level, designing scalable frontend and backend architectures, leading deep refactoring efforts, and making technical decisions that affect long-term maintainability and growth.
He has delivered complex products including a media intelligence platform with real-time analytics dashboards and AI-powered content aggregation, a digital pathology system for medical professionals with deep zoom visualization and collaborative annotation tools, an enterprise AI NLP platform deployed across AWS, GCP, and Azure, and a multi-chain cryptocurrency wallet supporting staking, DeFi protocols, and real-time portfolio tracking.
Oleksiy combines strong React and Next.js frontend architecture with Python and Node.js backend capability, working across WebSockets, GraphQL, REST APIs, and cloud infrastructure. He regularly leads frontend teams, establishes coding standards, drives performance optimization, and contributes to backend development using FastAPI and SQLAlchemy.
If your product needs an engineer who can own system architecture, lead technical decisions, and deliver production-ready full-stack platforms that scale without breaking, Oleksiy is the kind of developer who builds things right the first time 🚀
Download the CVHard skills
JavaScript
TypeScript
Python
Node.js
React
Next.js
Redux
Redux Toolkit
Zustand
RTK Query
React Query
React Hook Form
Formik
Tailwind CSS
Shadcn
Material UI
Ant Design
Bootstrap
Framer Motion
tRPC
GraphQL
WebSockets
Socket.IO
REST APIs
Express
Fastify
NestJS
Medusa.js
FastAPI
SQLAlchemy
Alembic
TypeORM
Prisma ORM
Web3
SQL
PostgreSQL
MySQL
SQLite
MS SQL Server
Redis
MongoDB
Firebase
Docker
Docker Compose
Terraform
Kubernetes
Nginx
Apache
AWS
GCP
Microservices Architecture
Software Architecture
Design Patterns
Technical Documentation
TDD
Tools
Git
GitHub
GitLab
Bitbucket
GitHub Actions
GitHub CI/CD
Postman
Jest
Vitest
Pytest
Cypress
Playwright
Storybook
CodeceptJS
MSW
React Testing Library
Sentry
ESLint
Prettier
Husky
Vite
Webpack
Turbopack
SWC
VS Code
WebStorm
Cursor
PyCharm
Sanity CMS
Cheerio
Selenium
BeautifulSoup
Scrapy
OpenAI
NextAuth
AG Grid Enterprise
AG Charts Enterprise
Recharts
OpenSeadragon
Annotorious
Soft skills
Architectural thinking
Technical leadership
Problem solving
Ownership
Communication
Team collaboration
Performance mindset
Continuous learning
Media Intelligence and Content Analysis Platform
Full Stack Developer
Project Description:
Built the entire frontend from scratch using Next.js and React with scalable, modular architecture. Developed real-time analytics dashboards with interactive visualizations, entity extraction, sentiment analysis, and content trend monitoring. Contributed to backend development using FastAPI and drove significant performance optimizations across the application.
Tools & Technologies:
Python, TypeScript, React, Next.js, Redux Toolkit, Socket.IO, Tailwind CSS, Radix UI, Shadcn, Framer Motion, AG Grid Enterprise, AG Charts Enterprise, Recharts, React Hook Form, Yup, Cypress, Jest, ESLint, Prettier, Husky, Sentry, NextAuth, RTK Query, Firebase, FastAPI, PostgreSQL, OpenAI, Google Cloud Platform
Digital Pathology Slide Viewer and Annotation Platform
Full Stack Developer
Project Description:
Led frontend development as Technical Lead for a digital pathology platform enabling pathologists to review, annotate, and collaborate on high-resolution whole slide images. Built the complete slide visualization and annotation system on top of OpenSeadragon with custom drawing tools, real-time collaborative annotations via Socket.IO, and performance optimization for handling hundreds of annotations simultaneously.
Tools & Technologies:
Python, TypeScript, React 19, Vite, Redux Toolkit, RTK Query, Material UI, Socket.IO, OpenSeadragon, Annotorious, React Hook Form, Zod, FastAPI, SQLAlchemy, PostgreSQL, Redis, Docker, Google Cloud Platform
AI SaaS Platform for Natural Language Understanding
Full Stack Developer
Project Description:
Developed a standalone Survey Service microservice using Next.js, built interactive NLP dashboards and reporting tools, and led the technical migration from React 16 to React 18. Established comprehensive testing infrastructure with Jest and Storybook, and contributed to backend development using FastAPI and Python.
Tools & Technologies:
Python, TypeScript, React 16, React 18, Next.js, Redux Toolkit, RTK Query, Tailwind CSS, Material UI, Ant Design, FastAPI, PostgreSQL, SQLAlchemy, Jest, Storybook
Multi-Chain Cryptocurrency Wallet Application
Full Stack Developer
Project Description:
Developed a cross-platform mobile cryptocurrency wallet supporting multi-chain staking, DeFi access, and real-time portfolio tracking across Ethereum, Polkadot, Cosmos, and other networks. Built the mobile application using Ionic and React, architected backend microservices with Node.js and Fastify, and implemented AWS infrastructure using Terraform with Redis caching and CI/CD pipelines.
Tools & Technologies:
Node.js, TypeScript, React, Ionic, Express, Fastify, PostgreSQL, Redis, AWS (EC2, RDS, S3, CloudWatch), Terraform, Docker
Master's Degree in Avionics
Igor Sikorsky Kyiv Polytechnic National Technical University
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