AI wellness platform · 2025–26
StayYoung
An AI-driven wellness platform — owned end to end, from the member app to the on-site AI coach to the subscription platform behind it.
role · Founding / lead full-stack engineerVisit StayYoung
The problem
Wellness guidance is generic and hard to stick with. StayYoung set out to deliver a personalised, conversational experience that meets people in Hebrew, on mobile, and adapts to them over time — which meant building a real product, not a landing page.
What I built
- Owned the full stack end to end: the member app, the AI coach, and the subscription, billing, and funnel platform that runs the business side.
- Built Tovi, the in-app AI coach — scoped prompts, streaming replies, and guardrails for safe, on-brand answers (its own case study).
- Designed a Hebrew-first, RTL-correct UI system on React + Tailwind + shadcn that stays fast on mobile.
- Modelled the data in PostgreSQL with row-level security and SECURITY DEFINER RPCs; auth, OTP, and notification flows wired through Supabase Edge Functions.
Impact
- Shipped the platform from zero to production as the core engineer.
- An AI coach answers member questions 24/7, with hard cost/rate guardrails.
- RTL-first design system keeps the mobile experience fast and consistent.
