Senior BackEnd Engineer

Senior Backend Engineer

AI Infrastructure x Fintech | High Growth Series A | Founders, Serial Entrepreneurs

London

£100K–£200K + Meaningful Equity Package (≈$160K vested over 4 years)

Omnis Partners is partnering with a venture-backed AI fintech building core infrastructure used by major financial institutions to operationalise AI safely, securely, and at scale.

Having recently closed Series A funding from globally recognised investors, the company is now scaling its engineering team to support rapid enterprise growth and increasing platform adoption.

This is an opportunity to join early, take ownership of critical backend systems, and help shape the technical foundations of a product already being deployed in production environments.

The Role

You’ll work on the backend systems underpinning a high-throughput AI platform used in regulated financial environments.

The engineering challenges are complex: large-scale data processing, distributed systems, production ML infrastructure, platform reliability, and security at enterprise standard.

This is a hands-on role for someone who enjoys building scalable systems from first principles and wants genuine influence over architecture and technical direction.

You’ll collaborate closely with product, ML, and infrastructure teams to design services that are fast, reliable, and capable of operating at significant scale.

️ What You’ll Be Working On

• Building scalable backend services and internal platform APIs
• Designing distributed systems and asynchronous processing workflows
• Developing robust data pipelines for large financial datasets
• Scaling PostgreSQL infrastructure and optimising database performance
• Shipping production-grade systems used directly by enterprise clients
• Improving reliability, monitoring, observability, and platform resilience
• Working alongside ML engineers to productionise AI capabilities
• Contributing to architecture decisions across backend and infrastructure
• Driving engineering best practices across performance, security, and scalability

What They’re Looking For

• Strong backend engineering experience in high-scale production environments
• Excellent Python skills (FastAPI, Flask, or Django)
• Deep understanding of PostgreSQL and database optimisation
• Experience designing distributed or event-driven systems
• Hands-on experience with Redis, queues, caching, and async workflows
• Cloud infrastructure experience (Azure, AWS, or GCP)
• Familiarity with Docker, Kubernetes, and CI/CD tooling
• Strong understanding of system reliability and secure engineering practices
• Comfortable operating in fast-moving, high-ownership teams

✔️ This environment will suit engineers who enjoy autonomy, pace, and solving difficult technical problems.

✔️ There’s ambiguity, priorities evolve quickly, and the expectations are high — but so is the opportunity to make a genuine impact.

✔️ If you enjoy ownership, building from the ground up, and working close to product and customers, this is the kind of role where you can accelerate quickly.