Senior Full-Stack Engineer (.NET / C#, Backend-Focused), Hybrid: Warsaw, Poland
Warsaw
Senior Full-Stack Engineer (Node.js, React, AI-first), Hybrid: Warsaw, Poland
Date published: 26.10.2026
Location:
WarsawPosition:
Full-StackLevel:
Senior
Department:
EngineeringProject details
We are looking for a Senior Full-Stack Engineer to join the team behind an AI-powered autonomous testing platform, built by a global leader in AI-powered test automation whose products are trusted by enterprises and startups worldwide, including many of the world’s largest companies.
This role involves end-to-end feature development across a TypeScript stack, from the Node.js backend to the React frontend, with an AI-first approach at every step of the development workflow. You’ll own features from technical design to production, work closely with Product and Design, and collaborate daily with the client’s engineering group as an integrated member of a hybrid team.
About the product.
The team builds an AI-powered platform that lets teams create, run, and maintain end-to-end tests with minimal manual effort. Instead of writing test code, users simply provide a URL: the platform crawls the application, automatically generates visual and functional tests, and organizes the results in a centralized dashboard.
Key responsibilities
- Design, build, and ship product features end to end across the TypeScript stack (Node.js and React).
- Own features from technical design through development, testing, release, and production monitoring.
- Think like a product owner: dig into the “why” behind features, balance user needs with technical tradeoffs, and take real ownership of the product experience.
- Work closely with Product, Design, and your teammates in Israel to turn requirements into clean, well-architected solutions.
- Contribute to architecture discussions, code reviews, and engineering best practices.
- Use Claude and agentic workflows as part of your everyday development process to move faster, and help build shared AI automations for the team.
Requirements
- 5+ years of hands-on software engineering experience in SaaS or product-driven companies, delivering features as a full-stack engineer on cross-functional product teams.
- 3+ years of production experience across the full stack with TypeScript, Node.js, and React.
- Hands-on experience using AI-assisted development tools in your daily workflow to accelerate development.
- Exceptional collaboration and communication skills, with a track record of partnering closely with product managers, designers, and fellow engineers.
- Proven success working in distributed or hybrid teams, collaborating daily across time zones (ideally with international engineering groups).
- Fluent written and spoken English, with the ability to explain complex technical ideas and tradeoffs clearly and confidently.
- A strong sense of ownership, self-direction, and an open, egoless communication style.
- Based in Warsaw and able to work from the office 3 days per week.
Will be a plus:
- Familiarity with test automation tools and frameworks (Playwright, Cypress, Selenium).
About Eastern Peak
We are a technology provider of custom hardware and software development solutions and digital transformation consulting services.
We help our clients adapt and evolve in the face of disruptive new technologies, dynamic global markets and rapidly changing regulatory environments. We do it by modernizing their legacy systems, automating business processes and creating the technological foundation to withstand and embrace continuous change.
We develop and deploy unique data analytics capabilities across their infrastructure and introduce competitive advantages by utilizing the advances in technology such as IoT, AI, Cloud, Big Data, AR/VR and others.