Backend Engineer (JVM)

Job description

Backend Engineer

SEED-Stage FinTech

Hybrid: City of London (3 days per week onsite)

£80,000 – £95,000 + Equity + Benefits

Did you know financial fraud costs the UK economy £200bn+ per year, accounting for over 40% of crime in England and Wales? This early-stage FinTech is on a mission to fight financial crime and reduce scams in online payments

High-ownership, mission-driven, working with sensitive financial data. This is critical infrastructure. When it fails, real people lose money.

What You’ll Do

• Build the APIs and UIs banks plug into their payment flows
• Connect the investigation engine to messy, real-world data (APIs, documents, scraped sources — most of it unstructured)
• Design the orchestration layer that gathers and evaluates evidence across heterogeneous systems
• Ship reliable, secure, observable production code
• Deploy and iterate on LLM-powered investigation flows (not just prototypes)
• Make smart build vs buy decisions and own the trade-offs

This isn’t a feature factory. You’ll design, build, ship, own.

Tech: Kotlin (open to any JVM background), Python, Terraform, Agentic AI, cloud-native, event-driven services

If you’ve built fault-tolerant, distributed systems before, tools matter less than judgement

You’ll Have

• 3+ years building production distributed systems in a startup environment, using backend languages like Java, Kotlin, Scala, Python, C++, Rust or Go
• Experience designing external-facing APIs and working with messy, unstructured data
• Shipped AI/ LLM systems beyond proof-of-concept
• Startup experience: comfortable in ambiguity, taken high ownership
• Strong instincts on trade-offs, speed vs correctness
• Computer Science degree or equivalent

Why Join?

• Work with a highly talented team of 8 other Engineers
• Real equity
• High-stakes technical challenges
• AI X distributed systems X regulated finance

If you want to build fast, reliable AI infrastructure that banks depend on, apply with your CV.

Extra information

Status

Open

Education Level

Secondary School

Location

City of London

Type of Contract

Full-time jobs

Published at

07-03-2026

Profession type

Accountancy

Full UK/EU driving license preferred

No

Car Preferred

No

Must be eligible to work in the EU

No

Cover Letter Required

No

Languages

English