💻 Job Title: AI (Infrastructure) Engineer
💰 Salary: up to £180k (DOE)
📈 Equity: up to 0.3% (DOE)
🌍 Location: fully remote anywhere in the UK (preference for proximity to London)
🔐 Company: AI Infrastructure / Developer Tooling
👥 Team: ~15
💸 Funding: ~$20m (Series A)
About the company
This category-defining start-up is building AI infrastructure and tooling that enables developers to run production AI agents inside their own products.
The platform is already running at genuine scale - tens of thousands of developers, hundreds of millions of agent executions per month, paying customers including some of the most active agent builders in the market.
The infrastructure challenges here are real: think reliable execution under extreme concurrency, orchestration at a level typically seen at companies 10x this size.
Their long-term vision is to become the default infrastructure layer for building and operating AI agents - similar to how certain developer tooling companies expanded from a single product into a suite that teams can't operate without.
About the role
This role sits at an unusual intersection: you'll be building agents on top of the platform, identifying where it falls short from a genuine power-user perspective, and then owning the fix - whether that means contributing code directly or driving it through the engineering team.
* Building production agent examples and internal tooling on top of the platform
* Identifying and owning gaps in the agent execution layer - observability, orchestration, memory, failure modes
* Shaping the product roadmap for agent infrastructure based on direct, hands-on experience
* Staying close to the agent tooling landscape - evaluating new frameworks and models as they emerge and forming real views
* Working directly with the founding team on architecture decisions that will affect thousands of development teams
* Contributing to upcoming infrastructure initiatives including sandboxed execution environments and LLM observability tooling
✅ Must have requirements:
* TypeScript proficiency - the codebase runs in TypeScript
* Proven track record of having built an agent harness from scratch, not just consuming wrappers but actually understanding the loop at a construction level
* Experience with multiple agent frameworks (LangChain, LangGraph, OpenAI Agents SDK, CrewAI, or similar) and genuine views on the trade-offs
* AI is embedded in your daily workflow beyond code generation
* Background in an early-stage startup - high autonomy is a requirement, not a preference
👍 Nice to haves:
* Experience evaluating and selecting models for production use cases, with clear measurement criteria
* Having shipped agent systems with defined success metrics and iterated from production data
* Research mindset - actively tracking releases, testing things and forming views
* Familiarity with the Vercel AI SDK
* Python framework experience (you'll mostly be working in TypeScript, but Python would be handy)
🛂 VISA sponsorship is NOT available for this role.