Backend Engineer

Overview

In this Backend Engineer role you will design multi-tenant data and workflow services in Python and FastAPI, and bridge between a Java/Spring core and Python AI services. You will work with an enterprise audience, ensuring permissions, audit trails, and safe AI outputs. You’ll join a UK core engineering team reporting to the Head of Engineering, delivering resilient services through CI/CD with a cross-border delivery organization. This is an opportunity to lay the foundations of an enterprise-grade platform for a sizable, growth-focused market.

Responsibilities

• Design REST and asynchronous services in Python 3.11+ with FastAPI
• Work at Java/Spring boundaries with PostgreSQL and async SQLAlchemy persistence
• Implement tenant isolation, RBAC, and configuration
• Version and evolve contracts between core and AI services
• Maintain unit and integration tests with pytest and pytest-asyncio
• Expose performance and reliability metrics with OpenTelemetry, logs, and alerts
• Ensure authentication, authorization, secrets, input validation, and audit trails
• Deploy and operate on AWS using EKS/ECS, RDS and S3 through Jenkins gates
• Improve queries, caching, throughput, and right-sizing
• Build queueing, rate limits and cost-aware orchestration for model calls

Key requirements

• 5+ years in backend engineering for production SaaS or platform systems
• Experience with multi-tenant or enterprise systems including isolation, permissions, and auditability
• Strong Python with FastAPI (or similar) and solid SQL/PostgreSQL
• Ability to work across Java/Spring service boundaries
• Production AWS experience, Git, CI/CD and Linux
• Experience with AI coding tools (Cursor or Claude Code)
• Degree in engineering, computer science or related field, or equivalent experience

• pace and accuracy
• cross-functional collaboration
• problem-solving under high-stakes constraints
• Python 3.11+
• FastAPI
• PostgreSQL

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