Senior Full Stack TypeScript Engineer – Fintech
Summary
Build and maintain high-performance fintech web apps using TypeScript, React, and Node.js, with a focus on scalable APIs, databases, and AI-assisted development.
Senior Full Stack TypeScript Engineer (Node.js / React)
We need a Senior Full Stack TypeScript Engineer to develop high-performance web applications and backend services, shaping the next generation of fintech solutions.
Company Overview: We are a leading fintech company with over 25 years of innovation in financial markets. Our platform connects participants in repo and securities financing, delivering real-time solutions that enable clients to trade efficiently, accurately, and competitively. We foster autonomous, agile, and technology-driven teams with a strong focus on product excellence, innovation, and collaboration.
Working model: Net hourly on B2B. This varies with experience and skills and grows alongside your development. A contract of employment is also possible (Poland). Remote work is supported; no commute, no dress code.
Responsibilities
- Develop and maintain high-performance web applications
- Build and maintain Node.js backend services
- Create modern React-based frontend interfaces
- Design and implement RESTful APIs
- Work with relational databases such as PostgreSQL or MySQL
- Optimize web performance and scalability
- Write unit, integration, and end‑to‑end tests
- Participate in code reviews and maintain high engineering standards
- Collaborate with engineers and product teams to deliver complex features
- Use AI‑assisted development tools while ensuring code quality and security
- Take ownership of features from concept to production
Qualifications
- Advanced React, HTML5, CSS skills
- Deep understanding of RESTful APIs (HTTP, JWT, OAuth)
- Experience with relational databases (PostgreSQL / MySQL)
- Proficiency with Git, Linux/Unix CLI, npm/pnpm
- Unit, integration, and E2E testing (Playwright, Cypress, etc.)
- Web performance optimisation and scalable system design
- Practical experience using AI‑assisted development tools (GitHub Copilot, Cursor, Claude, Gemini)
- Strong critical thinking to validate AI‑generated code for security, maintainability, and performance
- Code review, documentation, and mentoring skills
- Ability to take ownership of complex features and drive delivery
- Redux / Zustand / Context API experience
- Tailwind / Styled Components experience
- Docker / Terraform / AWS Lambda experience
- Load testing tools experience
- English – professional working proficiency
During the interview process, we discuss recruitment, our work, and what makes Scalac a unique place to work. Feel free to ask any questions about the company.