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Fullstack Mobile Developer (Kotlin Multiplatform)

Summary

Builds and maintains mobile apps and shared business logic with Kotlin Multiplatform, plus Java/Kotlin backend services using Spring Boot for fintech products.

Fullstack Mobile Developer (Kotlin Multiplatform)


We are looking for a Fullstack Mobile Developer to join a team building next-generation digital financial products used by customers at scale.

In this role, you will work across the entire product ecosystem — from mobile applications and shared mobile logic to backend services and production systems.

The team is moving towards a modern development approach based on:

  • smaller, highly autonomous teams;
  • stronger engineering ownership;
  • increased code reuse across platforms;
  • practical adoption of AI-powered development tools.

You don’t need to know everything from day one, we are looking for an engineer who is curious, hands-on, proactive, and eager to learn.

Location: Poland (Remote / Hybrid)
Work mode: Remote or Hybrid
Cooperation type: B2B Contract

Responsibilities

  • Develop and improve mobile features used by real customers.
  • Build shared business logic for mobile platforms using Kotlin Multiplatform (KMP).
  • Develop backend services and APIs using Java/Kotlin and Spring Boot.
  • Work with cloud infrastructure, CI/CD pipelines, monitoring, and production systems.
  • Improve application performance, reliability, security, and overall user experience.
  • Use AI development tools to support coding, testing, documentation, and troubleshooting.
  • Collaborate closely with Product, Design, Architecture, Security, and Platform teams.
  • Take ownership of features from design through production delivery.
  • Contribute to engineering best practices and mentor other developers.

Requirements

We are looking for a strong software engineer with broad technical expertise, not just experience with a single framework:

  • Strong experience in mobile application development.
  • Deep understanding of Android and iOS architecture patterns and components.
  • Strong knowledge of Kotlin and modern mobile application architecture.
  • Experience building production-grade applications with a focus on quality, performance, and maintainability.
  • Backend development experience with Java and Spring Boot.
  • Understanding of REST APIs, microservices, and event-driven architectures.
  • Experience with CI/CD pipelines, automated testing, and production support.
  • Ability to independently own features and drive them from concept to release.
  • Strong communication skills and ability to collaborate with multiple teams.

Cross-platform development experience

Our strategic direction is Kotlin Multiplatform (KMP), allowing us to share business logic while maintaining native-quality mobile experiences.

Experience with KMP is a strong advantage, but we also welcome candidates with strong backgrounds in other cross-platform technologies such as Flutter or React Native.

Nice to have

  • Experience working in a fast-paced and dynamic environment.
  • Strong problem-solving and system-thinking skills.
  • Proactive “can-do” mindset.
  • Excellent teamwork and communication skills.
  • Interest in modern development practices and AI-assisted engineering.


See also