Principal Product Engineer, React Native

Justzapp; Greater London; On-site; GBP 110,000 - 170,000; Full time

Benefits offered by this job

Equity package

Private health insurance

25 days holiday per year

Extended sick pay & parental leave

Job summary

Zapp is hiring a Principal Product Engineer to own the mobile and web experiences across iOS, Android, and web. You will lead AI‑driven patterns, set technical direction, and own delivery end‑to‑end in a fast‑moving quick‑commerce environment.

Based in London with hybrid on‑site presence (3+ days/week), you will work on a world‑class customer experience while shaping product strategy and engineering culture. Visa sponsorship is not available.

Qualifications

• 10+ years building production software across mobile, backend, frontend, or full‑stack.
• Deep React Native and Expo expertise across iOS and Android with B2C apps.
• Strong fundamentals: TypeScript proficiency.
• Ability to apply AI in product, share patterns, and drive adoption.

Responsibilities

• Build the mobile and web experiences using React Native and Expo across iOS, Android, and web.
• Lead AI in product: set direction, prototype, and bring the team.
• Own delivery end‑to‑end: design solution, ship mobile, write backend if needed, and productionise.

Skills

React Native

Expo

TypeScript

AI in product

Leadership

Performance optimization

Tools

NestJS

GraphQL

GCP

Firebase

Live Activities

Job description

Principal Product Engineer, React Native

Location: Nine Elms, London. Full time, hybrid with at least 3 days a week on site.

You’ll need the right to work in the UK and be based in London. We are not able to offer visa sponsorship for this role.

About Zapp

Zapp is building the future of convenience with a full stack approach to on-demand essential items, 24/7, delivered in minutes. Customer obsession is at the heart of everything we do, from app users to frontline staff to store workers. We are relentlessly focused on delighting our customers.

We are backed by the world's leading investors, and our team has scale-up and exit experience at companies such as Amazon, Deliveroo, Tesco, Stuart, and Just Eat. If you're ready to help build the world's most customer-focused company, get in touch.

Our Leadership Principles

• Creating Magic
• Taking Ownership
• Raising the Bar
• Winning Together
• Delivering with Speed

We are an AI-first company

We don't just build software. We build intelligent systems. From AI-assisted development workflows to LLM-powered product features, we expect every engineer to embrace and actively shape how AI changes what we ship and how we ship it. If you're the kind of engineer who gets excited by what's possible when agents, models, and great product sense meet, you'll feel at home here.

The Role

Join Zapp and take full lifecycle ownership of the apps our customers use every day. We're building a world-class experience across iOS, Android, and web, and you'll help us get there.

Quick commerce moves fast and lives in the real world. AI is changing how we build it. That's the part we love. We need engineers who are curious, energetic, and thrive at the front line of both.

What you'll do

• Build a world-class customer experience: develop the mobile and web experiences using React Native and Expo across iOS, Android, and web.
• Bring AI into how we build: use AI in your daily work, share patterns, and learn from others.
• Lead AI in product: set direction, prototype, and bring the team.
• Own delivery end-to-end: design solution, ship mobile, write backend if needed, and see to production.
• Own on‑call: be on rotation and stand behind production.
• Keep app fast and trusted: profile performance, harden releases, protect health.
• Set technical direction: own architecture, patterns, standards across mobile stack, mentor others.

You're a great fit if you

• Have deep engineering experience: 10+ years building production software across mobile, backend, frontend, or full‑stack.
• Have deep React Native and Expo expertise across iOS and Android with B2C apps.
• Strong fundamentals: confident and idiomatic in TypeScript.
• Use AI daily and share patterns.
• Think product, not just code; measure impact on customers.
• Production minded: grasp mobile performance, stability, release, security.
• Care about craft: design systems, attention to detail, product feel.
• Comfortable in uncertainty, move forward when path not clear.
• Test as you build: automated tests.
• Passionate about execution: curiosity, energy, habit.
• Excellent communicator: clear writing and speaking, love sharing.
• Force multiplier: impact on other engineers via patterns, reviews, people growth.

If most of these land for you, please apply. We hire on trajectory and curiosity as much as CV.

Even better if you know

• NestJS
• GraphQL (federation)
• GCP and DevOps (Firestore, Pub/Sub, Cloud Run, Firebase)
• Native iOS or Android (Swift, Kotlin); maintain custom Expo native module for Live Activities, Dynamic Island.
• React Native Web
• Quick commerce or similar domain.

You won't be a great fit if you

• Need a fully defined process and a large, structured team to do your best work.
• Chase technical perfection at the expense of real customer needs.
• Stall when the path forward is unclear, or wait to be told what to do.
• Want to stay strictly inside your specialty and avoid unfamiliar parts of stack.

What's the interview process like?

We aim to make our process clear, respectful of your time, and a real two-way conversation.

Stage 1 - Intro call (30 min). A short chat about your background and a chance for us to tell you more about Zapp, the team, and the role.

Stage 2 - Technical interview (90 min). Live coding with full access to any AI tooling you'd normally use, and we'll send you a boilerplate repository in advance so you can focus on the problem, not the setup.

Stage 3 - On‑site interview (2 hours, in person). A visit to our office: one hour of mobile architecture, and one hour with senior leadership on how you work, what you care about, and how you align with our Leadership Principles.

Stage 4 - Offer.

We verify your right to work in the UK and complete reference checks before the contract.

• Equity package, depending on experience.
• 25 days of holiday per year, plus all bank holidays.
• Private health insurance.
• Extended sick pay and maternity or paternity leave.