Principal Front-End Developer/Staff Engineer, React

We are looking for a Principal Front-End Developer/Staff Engineer from Ukraine with 10+ years of front-end development experience to join our partner’s development team in Europe. This is a fully remote, full-time, long-term freelance position.
You’ll work on an AI agentic workforce platform in a dynamic, startup-like environment where technical excellence, innovation, and ownership are highly valued. We’re looking for an experienced technical leader who can shape front-end architecture, drive engineering best practices, mentor developers, and translate complex product requirements into scalable, high-quality solutions.
Our partner is a global internet group and tech investor, building companies that empower people and create impact across sectors such as online classifieds, food delivery, fintech, education, healthcare, and social platforms.

What We’re Looking For
10+ years of front-end development experience, including extensive commercial experience with React.
Previous experience as a Lead Front-End Developer, Staff Engineer, Principal Engineer, or in a similar technical leadership role.
Deep expertise in React, TypeScript, modern JavaScript (ES6+), HTML5, and CSS3.
Strong experience with Tailwind CSS and modern React-based application development.
Proven ability to design scalable front-end architectures, reusable components, and maintainable design systems.
Hands-on experience integrating AI capabilities, LLM APIs, AI-powered features, or agentic workflows into production applications.
Strong understanding of UX/UI principles and the ability to translate product requirements and designs into intuitive user experiences.
Experience with state management, performance optimization, responsive design, and front-end testing.
Ability to make architectural decisions, establish coding standards, conduct code reviews, and mentor other engineers.
Experience working in agile product teams or startup environments, with a strong sense of ownership and autonomy.
Strong communication and collaboration skills, including the ability to work effectively with product managers, designers, and back-end engineers.

What You’ll Do
Lead front-end architecture and technical direction for a modern AI-powered platform.
Build and optimize production-ready applications using React, TypeScript, and Tailwind CSS.
Integrate AI capabilities and APIs into user-facing workflows, contributing to the development of intelligent, agentic experiences.
Establish front-end engineering standards, best practices, and scalable development patterns.
Design and maintain reusable component libraries and design systems.
Drive performance, accessibility, reliability, and maintainability across the front-end stack.
Collaborate closely with back-end engineers to define API contracts and deliver seamless end-to-end functionality.
Work with product managers and designers to turn business requirements into effective product experiences.
Provide technical leadership through code reviews, mentoring, architectural discussions, and knowledge sharing.
Take ownership of complex technical challenges and help the team make sound engineering decisions.

Nice to Have
Experience with AWS services such as S3, and CloudFront.
Experience building AI-first products, integrating LLM providers, or working with AI agents and orchestration frameworks.
Experience scaling front-end applications in high-growth product companies.

What We Offer
Long-term freelance engagement with hourly compensation.
Competitive rates reflecting your experience and technical expertise.
Fully remote work with flexible hours.
The opportunity to shape the architecture and technical direction of a cutting-edge AI agentic workforce platform.
Collaboration with a motivated international team and the opportunity to make a tangible impact on the product.

If you have extensive React and TypeScript experience, a strong technical leadership background, and hands-on experience integrating AI into production applications, we’d be happy to hear from you.