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I am a Senior Full-Stack Software Engineer with a passion for designing robust software architectures and delivering production-grade web applications. I specialize in JavaScript/TypeScript, RESTful API development, backend system design, and performance optimization. I’ve repeatedly refactored legacy systems to improve reliability and reduce technical debt, working closely with founders and senior stakeholders in agile settings. I thrive in collaborative environments where I can influence technical roadmaps and mentor teammates, delivering features faster while maintaining quality and maintainable codebases. I enjoy building scalable SaaS and AI-driven products from MVPs to high-traffic systems, and I’m always eager to learn new technologies and improve processes.…I am a Senior Full-Stack Software Engineer with a passion for designing robust software architectures and delivering production-grade web applications. I specialize in JavaScript/TypeScript, RESTful API development, backend system design, and performance optimization. I’ve repeatedly refactored legacy systems to improve reliability and reduce technical debt, working closely with founders and senior stakeholders in agile settings. I thrive in collaborative environments where I can influence technical roadmaps and mentor teammates, delivering features faster while maintaining quality and maintainable codebases. I enjoy building scalable SaaS and AI-driven products from MVPs to high-traffic systems, and I’m always eager to learn new technologies and improve processes.

Vladyslav Nakonechnyi

Full Stack Developer, Web Developer, Front-End Developer, +2

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I am a Senior Full-Stack Software Engineer with a passion for designing robust software architectures and delivering production-grade web applications. I specialize in JavaScript/TypeScript, RESTful API development, backend system design, and performance optimization. I’ve repeatedly refactored legacy systems to improve reliability and reduce technical debt, working closely with founders and senior stakeholders in agile settings. I thrive in collaborative environments where I can influence technical roadmaps and mentor teammates, delivering features faster while maintaining quality and maintainable codebases. I enjoy building scalable SaaS and AI-driven products from MVPs to high-traffic systems, and I’m always eager to learn new technologies and improve processes.…I am a Senior Full-Stack Software Engineer with a passion for designing robust software architectures and delivering production-grade web applications. I specialize in JavaScript/TypeScript, RESTful API development, backend system design, and performance optimization. I’ve repeatedly refactored legacy systems to improve reliability and reduce technical debt, working closely with founders and senior stakeholders in agile settings. I thrive in collaborative environments where I can influence technical roadmaps and mentor teammates, delivering features faster while maintaining quality and maintainable codebases. I enjoy building scalable SaaS and AI-driven products from MVPs to high-traffic systems, and I’m always eager to learn new technologies and improve processes.

Available to hire

I am a Senior Full-Stack Software Engineer with a passion for designing robust software architectures and delivering production-grade web applications. I specialize in JavaScript/TypeScript, RESTful API development, backend system design, and performance optimization. I’ve repeatedly refactored legacy systems to improve reliability and reduce technical debt, working closely with founders and senior stakeholders in agile settings.

I thrive in collaborative environments where I can influence technical roadmaps and mentor teammates, delivering features faster while maintaining quality and maintainable codebases. I enjoy building scalable SaaS and AI-driven products from MVPs to high-traffic systems, and I’m always eager to learn new technologies and improve processes.

Skills

Experience Level

Expert

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Expert

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Expert

Language

English

Fluent

Ukrainian

Fluent

Russian

Fluent

Work Experience

Software Engineer (Freelance) at Freelance

January 1, 2026 - Present

Designed end-to-end software architecture for SaaS and AI-driven products from MVP to production. Built RESTful APIs (Express.js) and backend automation pipelines integrating Large Language Models (LLMs). Reduced manual operational workload by ~30% through AI-driven workflow automation. Performed performance tuning (query optimization, caching, profiling), improving API response times by ~25–35%. Refactored legacy codebases to reduce technical debt and improve long-term maintainability. Authored internal technical documentation, API references, and onboarding guides for client teams. Collaborated directly with founders on technical roadmaps, enabling ~20–30% faster feature delivery.

Back End Engineer at Chaparral Labs Inc.

January 1, 2025 - December 1, 2025

Primary backend and platform engineer for a cloud-based proteomics analysis platform. Designed scalable backend services using Node.js (Express.js), Rust, Python, and TypeScript. Implemented RESTful APIs and selective GraphQL endpoints supporting data-intensive visualization workflows. Improved average API latency by ~35% through code refactoring, indexing strategies, and query optimization. Built CI/CD pipelines using Docker and Jenkins, increasing deployment frequency and reducing release risk. Applied security best practices for authentication, access control, and sensitive data handling. Authored API documentation and internal architectural diagrams to standardize backend development.

Trading Strategy Developer (Part-time) at Quantower

August 1, 2024 - February 1, 2025

Developed automated futures trading strategies processing real-time market data streams. Implemented order execution, position tracking, and risk-management logic. Reduced execution latency by ~20–25% through algorithm optimization and system tuning. Built backtesting pipelines to compare strategy performance against historical benchmarks. Analyzed KPIs including execution delay, drawdown, and win-rate to validate strategy effectiveness. Documented trading logic, assumptions, and performance metrics for reproducibility and review.

Frontend Engineer at Konstellation Data

December 1, 2023 - August 1, 2024

Developed a large-scale analytics dashboard using React and Node.js. Integrated RESTful APIs backed by PostgreSQL, BigQuery, Snowflake, and DBT. Delivered data-driven UI components supporting thousands of daily analytical queries. Improved frontend rendering performance by ~30% via memoization and component refactoring. Maintained ~99.9% dashboard uptime across production releases. Implemented CI/CD workflows and authored internal UI guidelines for analytics components.

Full Stack Engineer at RIKSEO

December 1, 2023 - July 1, 2024

Architected and deployed a suite of 150+ web tools using Vue.js and Firebase. Built scalable frontend and backend services supporting thousands of monthly active users. Integrated custom search pipelines improving SEO visibility and crawl performance. Implemented CI-based deployments, reducing production issues by ~40%. Applied performance optimization techniques to improve page load times by ~30%. Authored internal technical documentation and onboarding materials.

Fullstack Developer at Euristiq

September 1, 2020 - February 1, 2022

Developed and maintained production web applications using React, Next.js, and Node.js. Built backend services with Flask, Django, and FastAPI. Refactored legacy JavaScript codebases, reducing bug reports. Improved page performance and responsiveness across multiple client projects. Conducted code reviews and mentored junior developers on best practices. Created API documentation and internal development standards; delivered features across multiple projects in agile workflows.

Commit Swimming – Full Stack Developer at Commit Swimming

January 1, 2020 - January 1, 2021

Built team management, billing, and CMS-style platforms for competitive swim clubs.