React Developer (f/m/x)

249 - 331 USDNet per day - B2B
Other

React Developer (f/m/x)

Other
B2B Contract
B2B
Senior
Hybrid
249 - 331 USDNet per day - B2B

Job description

Join a team building a modern fintech platform that helps businesses manage company spending more efficiently. The project focuses on developing a financial product that enables seamless integration of financial tools—including corporate cards, expense management, and invoice processing—directly with partner ecosystems such as banks, accounting platforms, and HR systems. The platform empowers companies to automate financial operations, simplify reconciliation processes, and gain full real-time visibility into their spending.

Your tasks

  • Lead initiatives focused on designing, building, and maintaining scalable front-end applications primarily using React and TypeScript

  • Build modern, performant, and intuitive user interfaces for key areas of the fintech platform

  • Collaborate closely with cross-functional teams across backend engineering, product, and design to deliver scalable product solutions

  • Integrate front-end applications with microservices-based architectures and APIs (REST / GraphQL)

  • Analyze application performance and implement optimizations to ensure high responsiveness, reliability, and scalability

  • Participate in code reviews, architecture discussions, and post-mortems while mentoring other engineers

  • Proactively address technical debt and guide the team through technical challenges, refactoring initiatives, and architectural migrations

Requirements

  • At least 5 years of professional software engineering experience, including strong commercial experience with React

  • Strong expertise in TypeScript, modern JavaScript (ES6+), and building large-scale SPA applications

  • Solid experience designing scalable front-end architectures using component-based and modular design principles

  • Experience working with APIs and distributed systems in microservices-based environments

  • Hands-on experience with front-end testing frameworks (unit, integration, e2e) and observability/monitoring tools

  • Previous work with CI/CD pipelines, cloud environments such as AWS, and container orchestration platforms like Kubernetes

  • Strong problem-solving skills, ownership mindset, and passion for mentoring and elevating engineering teams

  • Professional English proficiency - minimum B2

  • Fluent in Polish required

  • Residing in Poland required

Nice-to-have requirements

  • Previous experience in fintech or building financial products

  • Understanding of payments, cards, expense management, or accounting-related domains

  • Experience working in a scale-up environment

  • Experience with GraphQL, SSR, performance optimization, or building design systems

Tech stack

    Polish

    C2

    English

    B2

    TypeScript

    advanced

    Microservices

    advanced

    Kubernetes

    advanced

    React.JS

    advanced

    Amazon AWS

    advanced

    Next.js

    nice to have

    Cypress / Playwright

    nice to have

    Design System

    nice to have

    GraphQL

    nice to have

Office location

About the company

Sii

Sii Polska to czołowy dostawca doradztwa technologicznego, transformacji cyfrowej oraz usług biznesowych i inżynieryjnych. Firma obecna jest na rynku od 2006 roku, zatrudnia ponad 7 500 ekspertów, jedenastokrotnie zdobył...
Company profile

React Developer (f/m/x)

249 - 331 USDNet per day - B2B
Summary of the offer

React Developer (f/m/x)

-, Poznań
Sii
249 - 331 USDNet per day - B2B
By applying, I consent to the processing of my personal data for the purpose of conducting the recruitment process. Wyrażam zgodę na przetwarzanie moich danych osobowych zamieszczonych w niniejszym CV przez Sii sp. z o.o. z siedzibą przy Al. Niepodle... MoreThis site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.