Principal Front-End Developer / Staff Engineer React / AI Product
Summary
Fully remote (Ukraine-based) 3-month contract for a Principal/Staff front-end engineer to lead React + TypeScript architecture of AI-powered web applications: building design systems, optimizing performance, and integrating AI/LLM APIs and agentic workflows into production.
Principal Front-End Developer / Staff Engineer (React) | AI Product | Remote
Location: Ukraine, Fully Remote
Employment: Full-time
Duration: 3 months
Start Date: ASAP
Seniority: Principal / Staff Engineer
English: Upper-Intermediate (B2)
Industry: AI / Software Development / Technology
About the Role
We are looking for an experienced Principal Front-End Developer / Staff Engineer (React) to lead the technical development of modern, scalable, AI-powered web applications.
This is a hands-on technical leadership role that combines advanced React engineering, front-end architecture, and the integration of AI/LLM capabilities into production applications.
You will take ownership of critical architectural decisions, establish engineering best practices, and collaborate with cross-functional teams to deliver high-quality solutions in a fast-paced product environment.
The ideal candidate is a senior technical expert who can balance strategic architectural thinking with hands-on development and contribute effectively from day one.
Key Responsibilities
Front-End Architecture & Development
Design and implement scalable, maintainable front-end architectures using React and TypeScript.
Develop high-performance, responsive web applications using modern JavaScript (ES6+), HTML5, CSS3, and Tailwind CSS.
Build reusable components, shared libraries, and design systems.
Define and implement effective state management strategies.
Optimize application performance, rendering efficiency, and user experience.
Ensure code quality, accessibility, maintainability, and test coverage.
AI Integration & Product Development
Integrate AI/LLM APIs into front-end applications.
Develop intuitive interfaces for AI-powered features and agentic workflows.
Collaborate with backend and AI engineers to integrate intelligent services into production applications.
Design user experiences for asynchronous AI interactions, streaming responses, and complex workflows.
Ensure reliable communication between front-end applications and AI-powered backend services.
Technical Leadership
Drive front-end architectural decisions and establish technical standards.
Conduct code reviews and mentor developers.
Identify and resolve complex technical challenges.
Improve development workflows, engineering practices, and application scalability.
Collaborate with product managers, designers, and backend engineers.
Take ownership of technical delivery and contribute to product-level decisions.
Requirements
10+ years of professional front-end development experience.
Extensive commercial experience with React and TypeScript.
Previous experience as a Lead Front-End Developer, Staff Engineer, Principal Engineer, or in a comparable technical leadership role.
Expert knowledge of JavaScript (ES6+), HTML5, and CSS3.
Strong hands-on experience with Tailwind CSS.
Deep understanding of front-end architecture and scalable application design.
Proven experience building reusable components and design systems.
Strong knowledge of state management patterns and libraries.
Experience with front-end performance optimization, testing, and debugging.
Hands-on experience integrating AI/LLM APIs or agentic workflows into production applications.
Experience working in Agile product teams or startup environments.
Strong problem-solving skills, technical ownership, and mentoring capabilities.
English B2 or higher.
Nice to Have
Experience with Agentic AI and AI-powered product interfaces.
Knowledge of Go or Python.
Experience with AWS services, particularly Lambda, S3, and CloudFront.
Experience with real-time applications, streaming APIs, or asynchronous workflows.
Familiarity with CI/CD pipelines and cloud deployment practices.
Experience building products from early-stage development through production.
What We Offer
Fully remote opportunity for candidates based in Ukraine.
Full-time engagement for 3 months.
Opportunity to work on modern AI-powered applications.
Significant technical ownership and architectural influence.
Collaboration with experienced engineering and product teams.
Fast-paced environment with challenging technical tasks.
Immediate start.
Interested?