Flutter Developer at WithU Holdings Limited

About URUNN

URUNN is a fast-growing running app redefining how everyday runners train, connect, and perform. Built with world-class runners including Sir Mo Farah and Charlotte Purdue, we’re on a mission to help every runner unlock their best self - with personalised insights, seamless tracking, and a community that truly motivates.

This is a rare chance to join URUNN at the ground floor - shaping the future of a global fitness platform that’s set to inspire millions to run with purpose.

Role Overview

We’re looking for a Mid-Weight Flutter Developer based in Portugal to join our engineering team. You’ll play a central role in developing new app features, refining user experience, and optimising performance. This is an exciting opportunity for someone who enjoys owning product features from concept to release, collaborating closely with designers and product teams, and building clean, scalable code.

What You’ll Do

• Build and maintain core features of the Urunn mobile app using Flutter (Dart).

• Collaborate with product designers, backend engineers, and founders to bring ideas to life.

• Implement UI/UX designs with attention to responsiveness, animation, and seamless user journeys

• Optimise app performance, memory usage, and offline capabilities.

• Integrate APIs and maintain data flow between the app and backend services.

• Participate in code reviews and technical planning.

• Contribute ideas for improving usability, engagement, and new product features.

• Troubleshoot bugs, prioritise fixes, and continuously improve overall app stability.

• 2-4 years of experience working with Flutter/Dart in a production environment.

• Experience working with REST APIs and Firebase.

• Strong knowledge of mobile architecture patterns and application lifecycle.

• Understanding of performance tuning, app profiling and debugging tools.

• Experience with automated testing, CI/CD pipelines, and app store deployment.

• A team player mindset, clear communication style, and proactive attitude.

• Fluency in English.
  

Nice to Have

• Experience with fitness, health-tracking, or wearable integration (Strava, Garmin, Apple HealthKit, Google Fit).

• Hands-on experience with animations and custom UI components.

• Familiarity with analytics tools (Mixpanel, Firebase Analytics, Rudderstack).

• Start-up experience and ability to thrive with ambiguity.

• Good understanding of backend/cloud systems (Firebase and GCP), Kotlin and Swift.
  

Location

🇵🇹 Portugal-based candidates only. Remote-friendly within Portugal