At Upside,, we’re not just shipping features - we’re partnering with ambitious companies across the globe to solve complex, meaningful problems through technology. We work in small, focused teams, combining engineering, product thinking, and design, to deliver outcomes, not just output.

Open-source is a strategic part of our work. We build and maintain a number of open-source projects that support our clients and internal R&D. Our latest release is Enthusiast, an AI Agent framework tailored for e-commerce use cases.

Role Overview:

We are seeking an experienced React Native Engineer to lead the design, development, and maintenance of high-quality digital platforms for global clients. In this role, you will play a pivotal part in delivering performant, scalable, and reliable web and mobile applications. You'll work closely with a cross-functional team of 3 to 9 developers, contributing to both frontend architecture and user experience across devices. Your insights will shape client-facing solutions and ensure technical excellence from concept to deployment.

Requirements

• Extensive commercial experience in building application with React Native.

• Deep understanding of the React Native ecosystem and experience working with TypeScript, mobile architecture patterns, and native integrations (iOS and Android).

• Hands-on experience with tools and libraries commonly used in React Native development, such as Expo, React Navigation, and testing frameworks.

• hands on experience with deploying apps to App Store and Google Play

  Solid FP/OOP skills.

• Practical experience with Continuous Integration/Continuous Deployment (CI/CD) practices and modern cloud environments.

• Strong consulting mindset - balancing technical excellence with client needs and communicating effectively with both technical and non-technical stakeholders.

• Fluent English, with clear written and verbal communication.

Bonus Points if you have:

• Exposure to accessibility and internationalization (i18n) in mobile apps.

• A good eye for UI/UX and experience collaborating with design teams.

• Experience with mobile-first animations and gesture handling (e.g. Reanimated, Moti, Lottie).

• Experience with native mobile development (Swift, Kotlin, Java)
  

Your responsibilities would be

• Developing complex mobile application - from architecture decisions to hands-on implementation.

• Work in autonomous teams (3-9 people) delivering mission-critical systems.

• Collaborate directly with technology leaders, founders, and domain experts to shape solutions that drive real business outcomes.

What We Offer

• Transparent progression path.

• Flexible work: office in Kraków, hybrid or remote from anywhere in Poland, with company on-sites.

• Additional paid days off beyond national holidays.

• A deeply collaborative, engineering-led company culture.

• Support for ongoing learning.

If you didn't find all the information you were looking for, have a look at our handbook - it covers a variety of different matters that could be important at this stage. If there's anything else we did not mention that you're interested in - share your thoughts with us careers@upsidelab.io

Salary:

Senior Engineer: 20 800 - 25 900 PLN net + VAT
Lead Engineer: >26 500 PLN net + VAT

Including additional days off

Location:

Office in Kraków, hybrid, fully-remote.