Fullstack Developer (m/f/d)

October 21, 2026

Office

Middle

Barcelona, Spain

Indeed

Keep in mind

Office-only work

Description

Fullstack Developer role based in Barcelona covering mobile applications built with React Native and TypeScript, plus backend services in .NET (C#). The position spans the whole delivery cycle: business logic and RESTful APIs, responsive mobile UI, automated tests and code reviews. Work is organised in small vertical slices behind feature flags, with direct collaboration between engineering, product design and product analytics inside a large European retail IT division.

Gender markers in the title: (m/f/d)

In accordance with European anti-discrimination legislation, this job is open to all candidates

Mmale

Ffemale

Ddiverse

Responsibilities

Own and deliver features end-to-end from business logic and backend endpoints to responsive mobile user interfaces
Build and evolve screens and user flows in React Native with TypeScript, ensuring clean architecture and solid performance across devices
Design, build and maintain RESTful APIs and decoupled services in .NET (C#) with reliable integration contracts
Write and maintain unit, integration and E2E tests so software reaches production with maximum stability
Partner directly with the Product Designer and Product Data Analyst without relying on managers as bridges
Break down complex epics into small functional slices supported by feature flags at a steady delivery pace
Participate in code reviews across frontend and backend with constructive and rigorous technical feedback

Requirements

At least 3-4 years designing, developing and maintaining production-grade mobile applications for iOS and Android
Solid hands-on experience with React Native and TypeScript in production applications
Proven experience designing, building and integrating RESTful APIs and backend services
Backend and API development expertise, preferably in C# / .NET
Practical experience with unit and integration testing frameworks such as Jest and xUnit/NUnit
Technical pragmatism and balanced judgment between clean extensible architecture and fast iterative delivery
Ability to articulate technical decisions with data and defend estimations constructively in technical debates
Nice to have: experience with event-driven architectures and message brokers such as NATS, Kafka or RabbitMQ
Nice to have: experience with Docker, Kubernetes or cloud deployment environments
Nice to have: knowledge of Infrastructure as Code technologies
Nice to have: hands-on experience with shared design systems and component libraries
Nice to have: familiarity with CI/CD pipelines such as Azure DevOps, GitHub Actions or Fastlane
Nice to have: understanding of observability, tracing and metric visualization with Prometheus and Grafana
Nice to have: practical familiarity with Xcode, Android Studio and the native bridge / NitroModules