Senior Full-Stack Engineer from Ukraine, based in Budva, Montenegro.
Building high-performance products from MVP to enterprise scale.
Open to remote worldwide, and ready to fly in for key product and architecture sessions.

• 16+ years in product engineering, delivery, and architecture.
• Frontend + backend + platform ownership with strong execution speed.
• Led teams up to 15 engineers and collaborated in organizations with 400+ developers.
• AI-assisted prototyping only. Final architecture, security, performance tuning, and production code: 100% human.

TypeScript, JavaScript, Node.js, PHP, Go

React, Next.js (App Router, SSR/SSG), Angular, Tailwind CSS, MUI, Chakra UI, Framer Motion, styled-components

NestJS, Express, REST, GraphQL, RBAC, SSO, multi-tenant SaaS, security hardening, high-load optimization

PostgreSQL, MySQL, MongoDB, Redis, SQLite, Supabase, Firebase

OpenAI, Anthropic, Gemini, Vercel AI SDK, tool-calling, Chrome/Edge extensions (MV3), Web3/smart contracts

Jest, RTL, Playwright, Cypress, GitHub Actions, CircleCI, Docker, Sentry, Logz.io

• High-load backend pipelines processing 1M+ records/day.
• Large data platforms and production clusters beyond 60TB.
• Enterprise SaaS modules with strong reliability and UX standards.
• Browser extension products with embedded AI assistants.

If you are building a high-load SaaS, AI-powered workflow, extension platform, or complex migration project, let's connect.

• Portfolio: yefimov.tech
• Email: val@yefimov.tech
• LinkedIn: linkedin.com/in/valyefimov
• Book a call: calendly.com/valyefimov/15min