Senior Software Engineer
Senior Software Engineer — Expansion numi | London (Hybrid, 3 days/week) · Central London
We're hiring a Senior Software Engineer to join the Expansion team at one of the most technically ambitious companies in commercial motor insurance.
Their mission is genuinely different — engineered to prevent accidents, not profit from them.
The opportunity
You won't just be writing code. You'll be the bridge between complex underwriting logic and the brokers and fleet managers who depend on it — playing a direct role in bringing new sectors like haulage and courier fleets onto the platform.
What you'll be doing
- Owning features end to end — design, deployment, and measuring impact
- Building and evolving backend microservices in a TypeScript monorepo (CQRS, Hexagonal Architecture)
- Designing events and projections that keep services decoupled as the product grows
- Extending a React-based internal Product Config UI used by underwriters and PMs
- Working across Lambda, API Gateway, EventBridge, SQS, S3, and CloudWatch
- Translating complex domain problems into sharply scoped, impactful deliverables alongside your PM
What you'll bring
- Expert TypeScript
- Proven experience with event-driven backend systems on AWS
- Hands-on with CQRS, event sourcing, projections, and Hexagonal Architecture
- React exposure useful; fintech, insurance, or regulated domain experience a bonus
What makes you right for this
You think about the customer outcome first and work backwards to the simplest solution. You're comfortable sitting with a stakeholder, understanding the real problem, and navigating ambiguity without waiting to be briefed.
This company actively wants to hear from candidates who come from backgrounds currently underrepresented in engineering.
What's on offer
Competitive salary · 25 days holiday + bank holidays · Private medical (incl. optical & mental health) · £1,500 L&D budget + 3 paid L&D days · Enhanced parental leave · Salary sacrifice schemes (gym, cycle, tech, nursery, EV)
This search is managed exclusively by numi. Reach out directly to apply or find out more.