b Overview /b p 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. /p b Responsibilities /b ul li Design REST and asynchronous services in Python 3.11+ with FastAPI /li li Work at Java/Spring boundaries with PostgreSQL and async SQLAlchemy persistence /li li Implement tenant isolation, RBAC, and configuration /li li Version and evolve contracts between core and AI services /li li Maintain unit and integration tests with pytest and pytest-asyncio /li li Expose performance and reliability metrics with OpenTelemetry, logs, and alerts /li li Ensure authentication, authorization, secrets, input validation, and audit trails /li li Deploy and operate on AWS using EKS/ECS, RDS and S3 through Jenkins gates /li li Improve queries, caching, throughput, and right-sizing /li li Build queueing, rate limits and cost-aware orchestration for model calls /li /ul b Key requirements /b ul li 5+ years in backend engineering for production SaaS or platform systems /li li Experience with multi-tenant or enterprise systems including isolation, permissions, and auditability /li li Strong Python with FastAPI (or similar) and solid SQL/PostgreSQL /li li Ability to work across Java/Spring service boundaries /li li Production AWS experience, Git, CI/CD and Linux /li li Experience with AI coding tools (Cursor or Claude Code) /li li Degree in engineering, computer science or related field, or equivalent experience /li /ul ul li pace and accuracy /li li cross-functional collaboration /li li problem-solving under high-stakes constraints /li li Python 3.11+ /li li FastAPI /li li PostgreSQL /li /ul
Backend Engineer employer: Oscar
Join a dynamic and innovative software and Business Intelligence organisation in Hertford, where you'll thrive in a hybrid work environment that promotes flexibility and collaboration. As a Data Consultant, you'll enjoy a varied role with opportunities for professional growth, including managing projects from inception to deployment and engaging with a European customer base. The company fosters a supportive culture that values continuous learning and offers exposure to exciting industry events, making it an excellent employer for those seeking meaningful and rewarding work.
