Senior Fullstack Mobile Developer (React Native, Supabase) - PT - Worldwide

Duration: 4–6 weeks initial (likely to extend based on fit)
Hours: 20–30 hrs/week (flexible, can flex up to 40 if candidate is available)
Location: Remote — open to Europe, Latin America, Africa, Asia Pacific
Client working hours: Founder works UK hours, often into the evening; some overlap with UK daytime preferred, not required.

About the company

The startup turns event/trade-show conversations into personalized, multi-channel sales follow-up. Reps scan a badge, the conversation gets transcribed, and generates tailored outreach (LinkedIn, email, SMS, call scripts) per contact instead of generic templated sequences.

Solo non-technical founder, MVP is live and 50+ company waitlist, and is targeting London trade shows this month/next for go-to-market.

What this role actually covers

The founder needs a hands-on engineer to:

• Review and stabilize the existing codebase — MVP was largely AI-generated; needs a real engineering review before it's commercially sellable to enterprise B2B clients.
• Build native iOS and Android apps (React Native) — current product is web-only; venue Wi-Fi is unreliable, so a proper app (not a browser tab) is required for usable on-site workflow at events.
• Implement Sign in with Apple and finish remaining integrations beyond the existing HubSpot connection.
• Move outreach generation from static to dynamic — currently outputs a fixed 5-touch sequence; needs to pull in external signals (LinkedIn activity, recent news/promotions, prior outreach analytics) to personalize each follow-up.
• Security review — GDPR compliance, groundwork for ISO certification, pen-test readiness. Founder is open to splitting this into a separate contract if the primary hire doesn't have strong security experience — flag this during interview rather than overstating it.

Tech stack

• Frontend/mobile: React, React Native, Expo, TypeScript, React Router
• Backend: Node.js, Supabase (Postgres)
• Other tools in use: Sentry, PostHog, HubSpot API
• Nice to have: blockchain payment integration experience

What we're looking for

• Strong TypeScript/React/React Native — able to take over and extend an existing AI-generated codebase, not just build greenfield
• Backend competency with Node.js + Supabase/Postgres
  Real experience shipping iOS/Android apps, including native integrations (Sign in with Apple, camera/badge scanning)
• Comfortable auditing someone else's (AI-assisted) code for security gaps — GDPR awareness a strong plus, ISO 27001 prep experience a bonus
• Able to work with a non-technical, fast-moving solo founder — proactively flag scope/architecture issues rather than just executing instructions
• Fluent English required; Spanish a plus — founder and family speak Spanish