Senior Backend Engineer

🔥 Senior Backend Engineer 🔥

💥 High-growth Series A AI Fintech | Enterprise-scale platform | Backed by Tier 1 investors 💥

📍 London

💸£100-£200K + $160k equity vested over 4 years

🚀 Series A backed by leading global venture investors

Omnis Partners is partnering with a rapidly scaling Series A AI fintech building enterprise-grade AI workflow infrastructure for global financial institutions.

This is a rare opportunity to join at a pivotal growth stage and help build the backend systems powering a production AI platform already trusted by major enterprise clients.

🚀The Opportunity

As a Senior Backend Engineer, you’ll help design and scale the core backend systems behind a high-performance AI platform operating in complex, regulated environments.

You’ll work across backend, data, and infrastructure domains alongside ML engineers and product teams to build systems that are secure, scalable, and built for enterprise-grade reliability.

This is a hands-on, high-impact role where engineering decisions directly shape product capability and scale.

🧩 What you’ll be doing

• Design, build, and scale backend services and APIs powering a production AI platform.

• Develop and optimise high-throughput data pipelines for large-scale financial datasets.

• Productionise ML models in collaboration with machine learning engineers.

• Design and optimise PostgreSQL schemas, queries, and performance at scale.

• Build secure, compliant systems aligned with SOC 2, GDPR, and regulated environments.

• Work on distributed systems using event-driven and asynchronous architectures.

• Improve system reliability, observability, and performance in production.

• Contribute to architecture discussions and mentor engineers within the team.

🔧 What they’re looking for

• 5+ years backend engineering experience building production-scale systems.

• Strong Python experience (FastAPI / Django / Flask).

• Deep PostgreSQL expertise (schema design, indexing, query optimisation).

• Strong understanding of distributed systems and microservices architecture.

• Experience with Redis, caching strategies, and async task queues (e.g. Celery).

• Cloud experience (Azure preferred, AWS/GCP also fine).

• Experience with Kubernetes, Docker, and CI/CD pipelines.

• Strong understanding of security, authentication, and compliance in production systems.

• Experience working in fast-paced, high-ownership environments.

💡Why this role

• Significant ownership over backend architecture and scalability.

• Opportunity to work on real-world AI systems at enterprise scale.

• Direct exposure to founders with multiple prior successful exits.

• High-growth environment where engineering decisions matter every day.

• Chance to help shape a category-defining AI platform at Series A stage.

⚠️ The reality

This is a high-intensity, fast-moving environment. Priorities and requirements can shift quickly.

You’ll be expected to operate with autonomy and strong technical judgement.

In return, you get real impact, ownership, and speed of progression.

Then this is one of the most compelling AI Engineering opportunities globally right now.