Senior Software Engineer

Member of Technical Staff - Software Engineering

Seed Stage Agentic Infras Start-up

Work directly with some of the world's largest AI Frontier Labs

Check you match the skill requirements for this role, as well as associated experience, then apply with your CV below.

London | Hybrid

Up to £150k + equity

We’re working with an early-stage AI startup building core infrastructure focused on AI evaluation, structured data workflows, and production-grade operational tooling for frontier AI systems.

The company is building the systems around model performance, combining human-in-the-loop workflows, evaluation tooling, quality control systems, and AI-assisted operations into a scalable platform used within high-stakes environments.

This is a genuine early-stage start-up environment: small team, high ownership, fast execution, minimal bureaucracy, and direct involvement in shaping both product and engineering direction.

This is a highly product-focused engineering role for a strong full-stack engineer who enjoys building complete products end-to-end.

You’ll help design and build the internal platform powering the company’s AI evaluation and data operations engine, including workflows, tooling, interfaces, review systems, and automation pipelines.

The ideal person will care just as much about product usability, workflows, and frontend experience as they do about backend systems and architecture.

You’ll work closely with founders and users to turn complex manual processes into scalable software products, rapidly iterating based on feedback in a fast-moving startup environment. xwzovoh

What You’ll Be Doing

• Build full-stack internal products for Agentic AI evaluation and structured data workflows
• Design intuitive user interfaces and operational tooling
• Develop systems for task routing, review pipelines, QA workflows, and validation
• Integrate LLMs into automation and evaluation pipelines
• Work directly with users to improve workflows and product experience
• Own features end-to-end across frontend, backend, and infrastructure
• Help shape engineering standards, architecture, and product direction as the company scales

What They’re Looking For

• Strong full stack SWE engineering capability across frontend and backend
• Experience building and shipping agentic AI products within early-stage startup environments
• Engineers who enjoy ambiguity, ownership, and rapid iteration
• Product-minded individuals who care about user experience and workflow design
• Comfortable operating without heavily defined requirements or large support structures
• Engineers who actively use AI tooling within their development workflows
• People who prefer fast-moving, high-impact environments over large corporate structures
• The environment will suit engineers who are pragmatic, product-oriented, and comfortable wearing multiple hats in a start-up setting.