Senior Full Stack TypeScript Engineer – Fintech

Scalac; Poland; Remote; PLN 165,000 - 248,000; Full time

Job summary

A leading fintech company in Poland seeks a Senior Full Stack TypeScript Engineer to develop high-performance web applications and backend services. You will work on building modern React-based interfaces and designing RESTful APIs while optimizing performance and scalability. The ideal candidate has advanced skills in React, a deep understanding of RESTful APIs, and experience with relational databases like PostgreSQL or MySQL. This role supports remote work and offers a flexible working model.

Qualifications

• Advanced skills in React, HTML5, and CSS.
• Deep understanding of RESTful APIs such as HTTP, JWT, and OAuth.
• Experience with PostgreSQL or MySQL databases.
• 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

Responsibilities

• Develop and maintain high-performance web applications.
• Build and maintain Node.js backend services.
• Design and implement RESTful APIs.
• 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.

Skills

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

Strong critical thinking

Code review, documentation, and mentoring skills

Ability to take ownership of complex features

Redux / Zustand / Context API experience

Tailwind / Styled Components experience

Docker / Terraform / AWS Lambda experience

Load testing tools experience

English – professional working proficiency

Tools

Git

Linux/Unix CLI

npm/pnpm

Docker

Terraform

AWS Lambda

CI/CD

Job description

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.