Yosef Alnajjar
A full-stack engineer who turns ambiguous, zero-to-one ideas into shipped, production-grade products, and the trust to run with them.
6 years across fintech, enterprise and pre-seed startups. Comfortable being the person who leads the team, decides the architecture, talks to customers, and ships it.
Pulse
A health app that explains your Apple Watch data against your own history, not a generic score, built to grow beyond Apple Watch to other wearables.
Why I built it
My Apple Watch collects a ton of data, but Apple Health never really explains what any of it means. I built Pulse to close that gap: it tells you plainly whether today is normal for you, judged against your own history rather than a generic score, and says so honestly when there isn't enough data to know yet. It started with Apple Watch, but it's built to grow into other wearables from here.
How it's built
React Native + TypeScript client reading HealthKit on-device; Supabase Edge Functions handle normalisation, rolling baselines and delta detection, with Postgres (RLS-scoped per user) for time-series aggregates behind one shared typed contract.
Chorus
Simulates how a message lands with 20 distinct AI personas across four audiences, before you send it.
Early engineer at a venture-backed fintech, owned architecture on a platform processing around $1B in deal value.
First full-time engineer at an early-stage startup, owned the full stack end-to-end, from mobile capture to services.
Sole backend engineer, architected an influencer-marketing SaaS platform from concept to production.
Helped migrate a legacy airline platform serving millions to AWS serverless, cutting time-to-booking by 60%.
Ambiguity is the job. I'd rather ship a narrow, honest version this week and learn from it than spend a month building for requirements nobody has confirmed. I take a founder's rough direction, turn it into a plan someone can build, and own it past launch, including the parts nobody assigned to me. When a request will cost more than it returns, I say so early, with the trade-off and an alternative, then commit fully to whatever we decide.