Backend Software Engineer – Python / FastAPI / Event-Driven Architecture (AI Agents / FinTech)

Role: Backend Software Engineer - Python

Location: London, UK (Hybrid)

Type: Full-time

Level: Mid to Senior

Salary: £70,000 – £100,000

About the Role

We’re building an AI-native financial platform designed for the next generation of intelligent systems. Instead of traditional dashboards and static workflows, our platform powers autonomous AI agents capable of executing financial operations, analysing real-time data streams, and orchestrating complex event-driven processes across modern financial infrastructure.

This is not another CRUD-heavy backend role. You’ll be helping architect the core infrastructure that allows AI agents to:

• Interpret and act on financial data in real time
• Trigger autonomous workflows across services
• Optimise decisions through simulation and probabilistic modelling
• Scale securely in high-trust financial environments

The company is founded by engineers from high-growth UK technology businesses and is backed by experienced FinTech operators. We’re building foundational infrastructure for AI-driven finance programmable, event-based, and intelligent by design.

If you care about clean architecture, functional design principles, and building systems that make real financial decisions this is for you.

Tech Environment

Backend: Python, FastAPI, Pydantic, PostgreSQL

Infrastructure: AWS, Docker, GitHub Actions, Kubernetes

Architecture: Event-driven systems, asynchronous processing, distributed services

Focus Areas: AI agent orchestration, financial data pipelines, real-time event processing

What You’ll Be Working On

• Designing backend services that power AI-driven financial agents
• Building low-latency APIs for financial data ingestion and execution workflows
• Architecting event-driven systems to support real-time decision engines
• Implementing robust data models for transactions, risk signals, and agent state
• Collaborating with AI/ML engineers to productionise agent behaviour
• Shipping secure, scalable services in a regulated FinTech environment
• Contributing to system design and architectural strategy at an early stage

What We’re Looking For

• 2+ years building production-grade backend systems
• Strong Python experience (FastAPI, Flask or similar frameworks)
• Experience designing event-driven or asynchronous systems
• Comfort working with financial data, transaction systems, or complex workflows
• Strong understanding of clean architecture and testable, composable code
• Ability to operate with autonomy in a fast-moving startup
• Interest in AI agents, autonomous systems, or the future of FinTech

Nice to Have

• Experience in FinTech, payments, trading systems, or financial infrastructure
• Exposure to AI/ML systems in production
• Knowledge of distributed systems design
• Familiarity with compliance, security, or high-trust environments

Backend Software Engineer – Python / FastAPI / Event-Driven Architecture (AI Agents / FinTech)