Senior Software Engineer

About Rayz

Rayz is a mission-driven, two-sided platform connecting verified grassroots changemakers with the supporters who back them. Changemakers share authentic, browser-captured video updates ("Captured Lives") and receive direct donations, turning scattered local trust into visible, recurring support. We're investor-backed, launching our first MVP cohort, and building toward a growth phase. The team is small and moves fast, the mission is real, and the technical bar is high because we handle donor money and personal data.

The role

We're hiring our first full time engineer to own the technology end to end: architecture, delivery, security, and technical strategy for a live donations platform. This is a hands-on, player-coach role, but hands-on in a modern sense. You'll direct and review AI-assisted delivery, make the architecture calls, and hold the quality bar, moving fast with a small team and the leverage that today's tools give it. You'll inherit a modern, well-built MVP (strict TypeScript, row-level security on every table, disciplined secrets handling) and be responsible for evolving it into a reliable, secure, scalable product, not rebuilding it.

The near-term product is a mobile-first web app. The roadmap moves to native mobile, so you'll lead that transition. Native mobile experience is a real requirement, not a bonus.

What you'll own

• Technical strategy tied to the business: turning our thesis and investor metrics into an engineering roadmap, and knowing which technical bets move conversion and retention.
• The full product stack: the mobile-first web app, the video pipeline (Mux), payments and payouts (Stripe, Wise), and the data model (Supabase / Postgres with row-level security).
• Security, privacy, and compliance: non-negotiable at a platform that holds and moves donor money and stores personal data. Data isolation, GDPR, Gift Aid, and the Fundraising Regulator Code.
• Reliability and scale: taking the product from a hand-held cohort MVP to a system that stays fast and correct under real load.
• The team: making the first engineering hires and setting the standard for review, testing, and documentation.
• Vendors and build-vs-buy: owning the calls across our managed-service stack. We buy well, and we're allergic to over-engineering.

What we're looking for

• Fluent with AI-assisted development: you use tools like Claude in your daily workflow, and you keep pace with fast-advancing AI capabilities to raise the leverage and quality of a small team.
• A senior, hands-on full-stack engineer who has led, at staff or principal level, or as an early-startup engineering lead, and who still loves to build.
• Deep TypeScript and modern React / Next.js (App Router, server components) on a serverless platform.
• Strong Postgres data modelling, including row-level security and multi-tenant data isolation. This is how we keep donor and changemaker data safe.
• Payments experience with Stripe, ideally in a regulated, fintech-adjacent, or donations context: webhooks, idempotency, subscriptions, money-movement correctness.
• A security-first instinct: you treat security as a feature, not a chore.
• Product and data literacy: you tie engineering work to real metrics and make the numbers move.
• Native mobile experience (React Native, or native iOS and Android): you've taken native apps to production before.
• Comfort with ambiguity, startup pace, high ownership, and low ego.

Bonus signals: video or streaming experience (Mux, WebRTC, or the browser MediaRecorder API) and mobile-web depth; experience in charity, impact, or fintech, and any exposure to fundraising regulation or Gift Aid.

The details

• Reports to the Founders.
• First senior technical leader on the team.
• £60,000-£80,000
• Remote, with regular in-person collaboration at our investor's office near Tottenham Court Road, London.
• Open to full-time or fractional for the right person. Let's talk about what works.