Senior Full Stack Engineer

About the Role

[Employer hidden] is looking for a Senior Full Stack Engineer with a frontend lean to join their product engineering team. You will report into the CTO and work embedded with a product manager and designer in a small, senior squad focused on user growth and the core consumer experience. The role involves rebuilding core user journeys, shipping growth experiments, and working across React (web) and React Native (mobile). You will be expected to reach into the backend when the feature demands it.

What You’ll Do

• Own User-Facing Features End-to-End: Take features from problem definition through to production across web and mobile.
• Rebuild Core Product Experiences: Redesign and re-engineer key user journeys — from item discovery and search through to the buying flow and post-purchase experience.
• Ship Growth Experiments: Build, run, and analyse A/B tests that drive user acquisition and activation.
• Build Across Web and Mobile: Work in React (web) and React Native (mobile) to deliver a seamless experience across platforms.
• Bridge Frontend and Backend: Reach into the Node.js/TypeScript backend when features require it.
• Shape UX with Design: Collaborate closely with product and design to define what gets built.
• Mentor and Elevate: Support more junior engineers through code reviews, pairing, and knowledge sharing.

What You Bring

• 3–6 years of professional frontend or full stack engineering experience.
• Strong proficiency in React, with experience or strong interest in React Native.
• Backend capability: comfortable working in Node.js/TypeScript.
• Data fluency: can write SQL, set up and interpret experiments, and use metrics to inform product decisions.
• Consumer tech background: experience at a marketplace, social platform, fintech, or consumer product company.
• Product engineering mindset: can articulate the business problem code solves.
• Startup or scale-up experience.
• Comfort with ambiguity.
• AI first 10x-er mindset.

Nice to Have

• Experience with growth engineering: experimentation platforms, A/B testing frameworks, funnel optimisation.
• Familiarity with international systems and distributed teams.
• Genuine excitement for building something from scratch.

This Role Isn’t for You If You Want:

• Pure UI-only work.
• Detailed specs handed to you before you start.
• A fully remote role (team works from London 3–4 days a week).
• A slow-moving, highly structured environment.
• Narrow specialisation with no cross-stack exposure.

The Practicalities

Location: London HQ — Heneage Street, E1 (Shoreditch / Aldgate East)

Work model: In-office, typically 3–4 days per week. Full-time in the office for your first six months, then genuine flexibility.

Level: Senior (L5)

Stage: Post-Series B, hyper-growth

Team: 100+ across London, India, and Pakistan

Stack: React, React Native, Node.js, TypeScript

How We Work

[Employer hidden] is an in-office company. Most of the team works from our London HQ 3–4 days a week. Performance and trust matter more than attendance. For your first six months, we’ll ask you to prioritise being in the office. After that, you’ll have genuine flexibility.

Our Values

Five values shape how we work at [Employer hidden]:

• Dream Big and Disrupt Yourself
• Absolute Ownership
• Curiosity Leads the Way
• Talk to the Customer
• Embrace Diversity

About [Employer hidden]

[Employer hidden] is a marketplace connecting resellers/vintage stores with vintage wholesalers from around the world. We empower the trendsetters empowering the circular and sustainable fashion movement.

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