Mobile Developer (React Native)

Nimbus Data Systems is a consulting-led digital transformation firm, founded in Warsaw in 2015 and now 70+ people strong. We work with mid-market and enterprise clients across Europe, the UK, and the US — helping them turn operational complexity into measurable business outcomes. We started as a mobile development shop. Over ten years, we built something different: a firm where every product is grounded in a real business case, and where engineering quality is as important as strategy. Our team is fully remote, our clients are international, and our standards are high. This role sits at the heart of that delivery. As Senior Mobile Developer, you will be embedded in a high-stakes client engagement - building a greenfield mobile app for a premium international luxury retail brand, from the first architectural decision to launch. The role and responsibilities: We are building a brand-new iOS and Android app — from scratch — as part of a major digital transformation for a premium international luxury retail brand. The app will serve 250k+ daily active users across global markets from the moment it launches. The product replaces static navigation with a dynamic, content-driven Feed ecosystem: personalised brand stories, exclusive offers, and live in-store updates, delivered with the engagement depth of social media. It is a greenfield project — no legacy code, no technical debt, full architectural ownership from day one. The app goes live in Q3. As Senior Mobile Developer, you will own the architecture and delivery of the app end to end. You will write code every day — this is a pure hands-on engineering role, with no team management responsibility. The client expects senior autonomy from the start. You will work alongside a senior cross-functional team: backend engineers, frontend web developers, UI/UX designers, and a PM. Architecture & technical leadership Architect from scratch: Design the React Native app structure, patterns, and coding standards that the entire project will build on. Define the content model: Work alongside FE Web developers to design the mobile content model powering dynamic, segmented delivery. Drive technical decisions: Own integration choices for CMS, DAM, and personalisation tooling — and be able to defend them. Feature development & integrations Integrate CMS, DAM & personalisation: Connect the tooling that delivers the right content to the right user — context-aware, segmented, and real-time. Implement deep linking: Build campaign-tied navigation flows and personalised user journeys across iOS and Android. Ship push notifications: Design and implement the full push notification layer, including deep links and campaign landing flows. Collaborate on features: Build and maintain new features together with backend engineers; work with UI/UX designers to assess feasibility and deliver high-quality UX. Performance & quality Optimise for scale: Own caching strategy, content-fetching architecture, and rendering performance for an app used by hundreds of thousands of people daily. Instrument analytics: Implement event tracking that supports personalisation decisions, A/B testing, and experimentation. Write quality code: Idiomatic, well-tested React Native — unit and component coverage as standard practice. Own distribution: Manage iOS and Android release cycles and store submissions. Requirements Must-have: React Native — 5+ years of professional experience building production iOS and Android apps from scratch. iOS and Android platforms — both, including distribution cycles, store submissions, and platform-specific behaviour. CMS & DAM integration — hands-on experience delivering dynamic, segmented content in mobile via headless CMS and DAM tooling. Personalisation & experimentation platforms — integrating decisioning tools, recommendation engines, or A/B testing systems into a live mobile product. Deep linking — production experience implementing campaign and personalised navigation flows. Push notifications — full implementation including deep links and campaign flows. REST API integration — connecting mobile apps to backend services at production scale. Performance optimisation — caching, content-fetching, and rendering strategies for personalised, high-traffic apps. Analytics & event tracking — instrumentation supporting personalisation and product experimentation. Testable code — appropriate unit and component test coverage as standard practice. English C1+ — written and spoken; direct communication with an international client team is a hard requirement. Nice to have: Experience with streaming APIs or AI-assisted feature integration. App analytics platforms such as Firebase or Amplitude. Consent management and third-party privacy tooling (GDPR). Mapping SDKs — Google Maps, Mapbox, or similar. Automated testing beyond unit and component level (E2E, integration). Broader JS ecosystem: Node.js , React, Next.js . A/B testing, feature flagging, and mobile attribution. Headless CMS architectures i