Senior Product Engineer

Justzapp; Greater London; On-site; GBP 90,000 - 130,000; Full time

Benefits offered by this job

Equity package

Private health insurance

25 days holiday + bank holidays

Job summary

Zapp is hiring a senior full-stack engineer to own the client-facing apps across iOS, Android, and web. You’ll develop features end-to-end, applying AI-enhanced patterns and shaping product experiences for fast-paced quick-commerce delivery.

You’ll work in a hybrid London-based setup and collaborate across backend, frontend, and infrastructure teams. We expect 5+ years of production software experience, strong TS/GraphQL/SQL fundamentals, and comfort with NestJS and React.

Qualifications

• Senior engineer with 5+ years building production software.
• Full-stack capability across backend, web, and infrastructure.
• Strong fundamentals in TypeScript, GraphQL, and SQL; experience with NestJS and React.
• Cloud/GCP experience, CI/CD, observability, and modern infra tooling.
• Daily use of AI in development and decision making.
• Product-driven mindset, not just code writing.
• Production-minded with API design, security, and reliability.
• Clear communication and collaborative approach.

Responsibilities

• Build a world-class customer experience across the stack, ship features end-to-end.
• Bring AI into daily work, share patterns to help the team move faster.
• Prototype and ship AI-enabled product features for the app.
• Own delivery end-to-end from design to production.
• Own on-call and support production in real time.
• Keep production fast, monitor latency, and harden release processes.
• Contribute to architectural discussions and code quality.

Skills

5+ years production software

TypeScript

GraphQL

SQL

NestJS / Node.js

React

Cloud/DevOps (GCP)

AI mindset

Job description

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 across the stack. Ship across backend, web, and infrastructure, and into mobile when features cross over.
• Bring AI into how we build. Use AI in your daily work. Share patterns that help the team move faster, and learn from what others discover.
• Help shape AI in our product. AI features in our app are still early. Spot the customer moments where AI can create magic, prototype them, and bring them to life.
• Own delivery end-to-end. Pick up a problem, design the solution, ship the work wherever the feature lives, and see it through to production.
• Own on-call. Be on the rotation, and stand behind what you ship in production.
• Keep production fast and trusted. Watch latency, harden release processes, and protect what customers rely on.
• Raise the bar for the team. Contribute to architectural discussions and the patterns that shape our codebase. Lift the people around you.

You're a great fit if you

• Senior engineering experience. 5+ years building production software.
• Full-stack range. Comfortable across backend, web, and infrastructure.
• Strong fundamentals. Confident with TypeScript, GraphQL, and SQL. At home in NestJS (or a similar Node.js framework) and React.
• Cloud and DevOps minded. Comfortable across GCP or a similar cloud, CI/CD, observability, and modern infrastructure tooling.
• Use AI daily. AI assistants are part of how you build. You bring back patterns that help others get more out of them too.
• Think product, not just code. You measure your work by what changed for the customer, not the lines of code shipped.
• Production minded. Solid grasp of API design, observability, scaling, reliability, and security.
• Care about craft. Clean APIs, attention to detail, and how the system feels to work in.
• Comfortable in uncertainty. You move forward when the path isn't clear, instead of waiting for someone to define it.
• Test as you build. Automated tests are how you ship code you trust.
• Passionate about execution. Curiosity, energy, and a habit of moving things forward.
• Excellent communicator. Clear in how you write and speak, and you love sharing what you learn.

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. Our backend is a NestJS service, and you'd feel at home when features need backend work.
• React Native. Our apps run on React Native and Expo. You'll touch them when features cross stack boundaries.
• GraphQL Federation. We run a federated gateway across multiple subgraphs, and federation experience makes schema and subgraph work easier.
• Distributed systems at scale. Event-driven patterns, async processing, real-time data flows.
• Infrastructure as code. Terraform, Kubernetes, or similar.
• Quick commerce or similar domain. Logistics, on-demand delivery, or another real-time, high-throughput customer-facing environment.

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 what the customer actually needs.
• Stall when the path forward isn't clear, or wait to be told what to do.
• Want to stay strictly inside your specialty and avoid unfamiliar parts of the 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 system design, 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.

Enhanced sick pay and maternity or paternity leave.