Senior Design Engineer

## About the Role This is an equity-only role, no salary at this stage. Compensation is structured around vesting milestones as PHOS scales. ## Mission Scale the face of the Personal Health Operating System. ## The Reality Check Most hire for pixels. PHOS is hiring for the experience. If you view design as just making things look pretty, you're in the wrong place. We're building the interface that makes complex health data feel simple, beautiful and empowering. If you're a 0 to 1 builder who thrives on solving the hard stuff, you're the one. ## The PHOS Story PHOS is the Personal Health Operating System. We are building the intelligence layer that sits between fragmented health data and human clarity. Our mission is to give people true autonomy over their health by synthesising wearables, biomarkers and behavioural insights into a single, agentic source of truth. The PHOS ecosystem was built solo by the founder in 8 weeks from the AWS serverless core to the high fidelity UI. Now, PHOS is moving from MVP to institutional scale. We need a Senior Design Engineer to own the experience so the founder can focus on leading PHOS as CEO, while continuing to build side by side with the core team. ## The Mission You are the architect of the PHOS Experience Layer. You will own the design system, component library and user interface that transforms complex health data into human clarity. PHOS is modular, a plug and play architecture designed to stay ahead of every advancement in the AI ecosystem. Your goal is to supercharge our output, ensuring we maintain extreme speed and consistency without ever needing a bloated team. ## Tech Stack - Frontend: React Native (Expo), TypeScript (strict mode), Expo Router - Design System: Custom PHOS brand system (Jost, Open Sans, DM Serif typography), atomic design patterns - Animation: React Native Reanimated, React Native Gesture Handler - UI Libraries: Expo Vector Icons, Lucide, custom Coolicons icon system - State Management: React Hooks + Context, custom theme system - Design Tools: Figma (Variables, Auto Layout, Dev Mode) - Platform: iOS, Android, Web (cross-platform) - Backend Integration: REST APIs, AWS Cognito authentication - Compliance: HIPAA/GDPR baseline (all UI must be privacy-first and accessible) ## What You'll Own - **PHOS Brand System**: Own and evolve the PHOS design system across the brand. You'll maintain brand consistency while creating interfaces that feel like infrastructure, not decoration. Every design decision should feel intentional and aligned with PHOS's "infrared portals for human ascension" aesthetic. - **Design-to-Code Parity**: Maintaining a premium component library where Design = Dev. You use Figma variables and tokens directly in the codebase. You don't hand off designs, you implement them. Figma is your starting point, code is your finish line. - **User Experience Architecture**: Design and implement interfaces that make complex health data feel simple. You'll create intuitive flows for health metrics, AI conversations and data visualization. Every interaction should feel effortless and empowering, not clinical or overwhelming. - **Component Library**: Build and maintain a production grade component library using atomic design principles. Your components will be used across the entire platform, from health dashboards to AI chat interfaces. - **Health Data Visualization**: Design and implement beautiful, meaningful visualisations for health metrics, trends and insights. You'll work with real-time data from wearables and make it feel human, not clinical. Turn numbers into narratives. The Vitality dashboard is your canvas. - **Polish & Theme System**: Own micro-interactions, animations, and the dark/light mode theme system. Implement Reanimated and Gesture Handler interactions that feel alive, haptics, spring physics, 60fps experiences. Ensure the PHOS brand aesthetic carries through seamlessly across all modes. Smooth is not optional. - **Holistic Synergy**: You don't just consume APIs, you co-design them with the Backend Architect to ensure data structures allow for the fastest possible UI responses and optimistic updates. You understand how a frontend change affects the backend and vice versa. We move in unison, with minimal rework. You think full-stack even if you're frontend-focused. - **Quality & Compliance**: Ensure the app handles data sync states (loading, partial data, errors) with grace and clear visual feedback. Never let the user feel a lag in the intelligence. All interfaces must meet WCAG standards and HIPAA/GDPR baseline requirements. Health data must be accessible to everyone, regardless of ability. You build for humans, not just users. - **Cross Platform Excellence**: Ensure pixel perfect experiences across iOS, Android and Web. You understand platform conventions but aren't afraid to push boundaries. React Native is your canvas, but you think native first. - **Team Player**: You don't build in a vacuum, you build to win together. You are a person who always considers how your choices impact the rest of the team, proactively looking for ways to make everyone's job easier, better and more efficient. ## Who You Are - **Character over CV**: We don't care about your degree. We care if you've shipped high-fidelity products from scratch. - **Design Excellence + Technical Depth**: You've built or maintained design systems before. You understand atomic design, design tokens and how to scale UI components. You can code your designs, not just design them. You understand the bridge between Figma variables and production code. You have a strong design sense and the engineering skills to implement it. You find bugs before users do. You have a portfolio of live apps, not just mockups. You understand the balance between beautiful design and performant code. - **Technical Stack**: You're fluent in React Native (Expo), TypeScript (strict mode) and modern React patterns. You understand Expo Router, React Navigation and React Native performance optimisation. You've built design systems and component libraries in production.