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Senior Full Stack Engineer | AI/FinTech | £150k + Equity

IO AssociatesLondon🇬🇧United KingdomPosted 1 Sept 2026

Quick Overview

Seniority
Mid Senior
Employment type
Full Time
Work mode
Hybrid
Location
London, United Kingdom
ReactReact Native

Job Description

Senior Full Stack Engineer | AI/FinTech | £150k + Equity

Most personal finance products are very good at telling you where your money went.

What if one could tell you what to do next?

I'm working with an early-stage AI FinTech that has recently closed its pre-seed round and is building an AI-powered financial co-pilot.

They're now looking for one of their first senior engineering hires.

This isn't a role where you'll inherit a mature platform, a backlog and six layers of approval.

You'll be Engineer /, working directly with the founders to turn an early product into something people genuinely trust with their financial decisions.

You'll be responsible for things like:

Building across the full stack, including React Native on the Front End
Making early architectural and technology decisions
Working with financial data, account aggregation and open banking integrations
Building the AI layer that turns financial information into useful actions
Helping shape the product, rather than simply being handed tickets
Setting technical standards that future engineering hires will build on

They're deliberately keeping the technical requirements broad.

What matters more is that you're a very strong full-stack engineer who has built products in demanding environments and is comfortable operating with ambiguity.

Experience within a recognised technology company, high-growth startup or FinTech would be particularly interesting. Exposure to AI/LLMs, financial data or open banking would be a bonus.

You'll need the appetite for early-stage life too. There's no Legacy codebase holding you back, but equally, there's nowhere to hide when something needs figuring out.

£150k + meaningful equity
Remote, but London-based
Pre-seed, recently funded
Engineer /

If you're a senior engineer who likes the idea of getting in early enough to genuinely influence what gets built and how it gets built, drop me a message.

Equally, if someone immediately came to mind while reading this, I'd appreciate an introduction.

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