Full-Stack Developer needed (React native)

This is early — we're looking for the right developer to help shape our app from close to day one, not join a large existing team. The role We're looking for a full-stack developer to lead build on the first modules of Skalr OS, working directly with the founder. You'll be one of the first developers on this product, with real input into architecture and technical decisions rather than just executing a fixed spec. What you'll be building (early scope): A patient/client retention dashboard — flagging at-risk or lapsed contacts, prioritising outreach A performance attribution module — tracking which staff member converts which lead, on which service/treatment, through to outcome (not just marketing-source tracking, but a layer beyond it) Core architecture decisions on data model, auth, and structure that will need to support multiple clients over time, not just one We're intentionally keeping full scope and roadmap details for direct conversation with shortlisted applicants — happy to go deeper once we're talking. What you'll need Must have: Strong full-stack experience — React front-end, solid backend/API experience, comfortable designing your own database schema and data model Experience building multi-user, role-based software (this product has distinct views/permissions for owners vs. staff — not a single-user app) Ability to design with future multi-tenancy in mind (multiple clients on one platform eventually) Comfortable working directly with a non-technical founder — translating business requirements into architecture yourself Strongly preferred: Experience with healthcare, client/patient data, or any regulated-data environment (data handling matters here — even indirect patient/treatment data) Experience integrating with third-party CRM or booking system APIs/webhooks Prior experience in an early-stage product environment, comfortable with evolving scope Nice to have: Experience with AI/LLM-integrated products Prior work on vertical SaaS for a specific industry, not just generic CRUD apps How we'll work together Starts as a contract engagement at standard Upwork rates — we'll agree scope on a small paid trial task first before a longer commitment Staged, module-by-module delivery rather than one big launch, so we can validate each piece as it ships Direct line to the founder — fast decisions, real input, no layers of process to wade through This has genuine potential to grow into a full-time role as the product proves out — we're building toward a bigger vision here, and want a developer who wants to grow with it, not just complete a gig To apply, please include: Links to 2–3 relevant projects — ideally something with a non-trivial data model or multi-user permissions structure A brief answer: how would you approach designing a data model that needs to work for one client now, but multiple clients later — build multi-tenant from day one, or retrofit it later? Why? Any experience with client/patient or otherwise regulated data Your availability (hours/week) and whether you'd be open to a paid trial task before a longer engagement Whether you're open to this growing into a full-time role over time