Python Senior Engineer - Hybrid - Inside IR35
Location: London, UK
Contract Type: 12-Month Contract (Inside IR35)
Working Model: Hybrid (2 days onsite per week)
Rate: Up to £425 per day
Positions Available: 2
About the Role
is hiring a Python Senior Engineer to join the Recommendations team supporting the AI Stylist experience - an AI-powered platform combining conversational AI with recommendation systems.
This role focuses on building and improving customer-facing AI services, with particular emphasis on evaluation frameworks, recommendation quality, and production reliability.
You will work closely with engineering, data science, and product teams to develop scalable AI-driven solutions used in live environments.
Key Responsibilities
- Build and maintain AI-powered services using Python
- Design and implement evaluation frameworks for LLM-based systems
- Improve AI output quality through structured evaluations and testing
- Apply techniques such as LLM-as-a-Judge for response assessment
- Work with non-deterministic AI systems in production environments
- Integrate AI services into broader APIs and platform ecosystems
- Support system reliability, observability, and performance
- Collaborate with data scientists on prompts, models, and evaluation strategies
- Participate in on-call support when required
Required Skills & Experience
- Strong Python engineering experience in production environments
- Experience building AI-enabled applications, recommendation systems, or conversational platforms
- Hands-on experience with LLM or AI evaluation frameworks
- Strong understanding of non-deterministic AI system behaviour
- Ability to design meaningful evaluations and improve system quality over time
- Experience working in cross-functional engineering and product teams
Desirable Skills
- Experience with Azure AI services or similar cloud AI platforms
- Familiarity with OpenAI or similar AI SDKs
- Exposure to distributed systems and infrastructure tooling
- Experience with Terraform or Kafka