Senior React Native Developer (f/m/x)

Senior React Native Developer (f/m/x)

Miejsce pracy: Warszawa

Technologies we use

Expected

• React Native
• TypeScript
• MobX
• React Hooks
• React Query/ TanStack Query
• React Native Reanimated
• Axios REST APIs
• Apollo Client GraphQL
• GitHub Actions
• Shopify FlashList

About the project

Join one of Europe's largest mobile platforms, delivering digital services used by millions of users across multiple countries in Europe and North America. Built on a multi-module architecture, the platform enables rapid product development, high code reusability, and continuous expansion into new business areas.

As a Senior React Native Developer, you will play a key role in shaping the architecture of a big mobile ecosystem, driving technical decisions, mentoring other engineers, and delivering high-quality solutions at scale.

This is how we organize our work

This is how we work

• scrum
• kanban

Your responsibilities

• Design, develop, and maintain complex mobile applications using React Native and TypeScript
• Drive architectural decisions and contribute to the evolution of our multi-module platform
• Lead technical discussions and participate in solution design
• Review code, mentor team members, and promote engineering best practices
• Collaborate closely with Product Owners, UX Designers, Backend Engineers, QA Engineers, and Architects
• Improve application performance, reliability, scalability, and maintainability
• Contribute to CI/CD processes and development tooling
• Support the integration of native mobile capabilities and third-party services
• Identify technical debt and proactively drive improvements across the codebase

Our requirements

• At least 5 years of commercial software development experience, including at least 4 years with React Native
• Proven track record of building and maintaining large-scale mobile applications
• Strong expertise in TypeScript, modern JavaScript, and React Hooks
• Solid understanding of modular and multi-module application architecture
• Hands-on experience with MobX and React Query (TanStack Query)
• Knowledge of native mobile development concepts and creating native modules for iOS and Android
• Practical experience with REST APIs, GraphQL, and form management solutions
• English and Polish proficiency at B2 level or higher
• Residing in Poland required

Optional

• Payment integrations and mobile wallet solutions
• Geolocation and location-based services
• Firebase services and analytics
• Mobile security best practices
• Observability and monitoring tools
• Background in large-scale international products
• Agile delivery experience (Scrum/Kanban)

What we offer

• Great Place to Work since 2015 - it’s thanks to feedback from our workers that we get this special title and constantly implement new ideas
• Employment stability - revenue of PLN 2.1BN, no debts, since 2006 on the market
• We share the profit with Workers - over PLN 76M has already been allocated for this aim since 2022
• Attractive benefits package - private healthcare, benefits cafeteria platform, car discounts and more
• Comfortable workplace – class A offices or remote work
• Dozens of fascinating projects for prestigious brands from all over the world – you can change them thanks to Job Changer application
• PLN 1 000 000 per year for your ideas - with this amount, we support the passions and voluntary actions of our workers
• Investment in your growth – meetups, webinars, training platform and technology blog – you choose
• Fantastic atmosphere created by all Sii Power People

Recruitment stages

• Send your CV
• Talk to us about your expectations
• Learn more about our projects and choose the best
• Start your adventure with Sii!

Sii Sp. z o.o.

Sii is the leading technology consulting, digital transformation, engineering, and business services vendor in Poland. We already employ more than 7 300 professionals and implement projects in a variety of industries for clients from many countries around the world. The Great Place to Work title, won 10 times in a row, proves that at Sii, we create a friendly work environment.

Sii ensures that all employment-related decisions are made solely on the basis of qualifications and competencies. We are committed to equal treatment of all individuals, regardless of any protected characteristics, and promoting a diverse and inclusive work environment.