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# Principal Mobile-First Fullstack Engineer (Agentic Ai)

- **Company:** Sklum
- **Location:** Madrid, Spain
- **Contract:** Permanent contract
- **Skills:** Next.js, ReactJS, Backend, React Native, Virtual Agents
- **Published:** September 19, 2026
- **Apply:** https://www.buscojobs.com.es/principal-mobile-first-fullstack-engineer-agentic-ai-en-madrid-ID-370493375

## About the Role

We value deep React Native expertise, strong backend API design, and experience with web tech (React/Next.js).
English fluency and cross?cultural collaboration are essential.
#J-*****-Ljbffr

## Description

SKLUM is building a mobile-first fullstack app.You will be a hands-on principal engineer guiding the mobile experience from React Native to backend services, collaborating with backend and data teams to ship features end-to-end.We value deep React Native expertise, strong backend API design, and experience with web tech (React/Next.js).English fluency and cross?cultural collaboration are essential.#J-*****-Ljbffr