Lead / Principal AI Engineer

Location: London, United Kingdom; hybrid work with required in-office days

Company

hirify.global, part of WPP, combines engineering, creativity and innovation to build intelligent digital products, platforms and experiences for ambitious brands.

What you will do

• Architect, develop and deploy production-ready AI systems, including agentic workflows, multi-agent orchestration, RAG and intelligent automation.
• Lead the technical design and implementation of secure, scalable and maintainable AI-powered products, applications and platforms.
• Design agent tools, APIs, MCP interfaces, backend services and integration layers for enterprise systems, databases and external services.
• Build compound AI architectures, evaluation frameworks, automated testing, guardrails and observability for model quality and operational performance.
• Establish CI/CD practices and optimize token usage, caching, latency, rate limits, fallback mechanisms and graceful degradation.
• Provide hands-on technical leadership while collaborating with engineering, creative, strategy, UX, product and client teams.

Requirements

• Significant backend, platform or software engineering experience, including distributed systems, microservices, asynchronous processing, API architecture and cloud infrastructure.
• Proven hands-on experience designing, deploying and maintaining generative AI or agentic systems in production, with commercially deployed AI engineering solutions.
• Advanced proficiency in Python and/or TypeScript/Node.js, with a focus on clean, testable and maintainable production code.
• Strong practical understanding of LLM architectures, agentic workflows, tool calling, RAG, embeddings, vector databases and hybrid retrieval.
• Experience with agent orchestration frameworks such as LangGraph, CrewAI, AutoGen, Vercel AI SDK or custom-built solutions.
• Experience developing AI evaluation and observability capabilities, automated unit, integration and regression testing, and CI/CD pipelines for non-deterministic AI systems.
• Strong understanding of software architecture, security, authentication, data management, enterprise integration patterns, cloud infrastructure and AI model ecosystems.
• Understanding of modern digital product development, including web applications, headless CMS platforms, APIs and front-end technologies.
• Ability to balance technical ambition with cost, latency, performance, security and maintainability; communicate complex concepts to clients and non-technical stakeholders.
• Experience in a digital agency, technology consultancy or product-led environment, collaborating across multidisciplinary teams and managing client expectations.
• Comfort taking ownership of technical architecture while remaining actively involved in hands-on engineering and delivery.

Nice to have

• Experience fine-tuning smaller or open-weight models such as Llama or Mistral for domain-specific applications.
• Experience with design-to-code workflows, Figma integrations, design systems or generative user interfaces.

Culture & Benefits

• Hybrid work model with required in-office days to support creativity, collaboration and connection.
• Accommodations or additional flexibility can be discussed during the interview process.
• Benefits are available through hirify.global's London studio offering.
• Equal opportunity workplace committed to respect, inclusion and equal career opportunities.

Hiring process

• The job post is no longer open to applicants.