About the Role
This is a rare opportunity to join as a Founding Engineer at a fast-moving, Seed-stage AI infrastructure startup building the backbone for the next generation of AI products — from coding assistants to agent orchestration systems and beyond.
You'll work directly alongside the founders to shape the company's technical direction from the ground up. If you're motivated by deep ownership, greenfield architecture decisions, and the kind of impact that only comes at the earliest stage of a company, this role is built for you.
What You'll Do
Design, build, and own core backend infrastructure powering a high-throughput, production-grade AI gateway serving billions of tokens per day.
Architect and evolve a pragmatic microservices system — including a core LLM gateway in Go and auxiliary ML/AI services in Python.
Make critical decisions around distributed systems design, database selection, caching strategies, and API platform architecture.
Profile and optimize performance for high-traffic, latency-sensitive systems (sub-20ms SLAs).
Work hands-on with Kubernetes to deploy, manage, and scale services reliably.
Redefine and evolve the tech stack as the product and team grow — you will be a key voice in those decisions.
Collaborate directly with founders to translate product vision into robust, scalable engineering solutions.
What We're Looking For
Required:
5+ years of experience building backend services using a compiled language — Go (Golang) strongly preferred.
Strong experience in distributed systems design and scalability.
Hands-on Kubernetes expertise in production environments.
Deep knowledge of SQL/NoSQL databases and caching layers — and the judgment to choose the right tool for the job.
Experience building or designing high-quality API platforms.
Experience with performance profiling and optimization for high-traffic systems.
Prior experience at an early-stage startup or on greenfield/founding engineering projects.
Strong understanding of concurrency patterns and how to apply them correctly.
The ability to balance pragmatism with quality — you know that "minimal" is not the same as "broken".
A self-starter mindset: you've taught yourself new technologies before and are eager to do it again.
Nice to Have:
Familiarity with LLM APIs, AI inference infrastructure, or observability tooling.
Experience with semantic caching, PII detection, or content governance systems.
Background at companies operating in the API gateway, developer tooling, or AI/ML infrastructure space (e.g. OpenRouter, Kong, Portkey, Helicone, Cloudflare, Vercel, or similar).
Compensation & Benefits
Competitive total compensation package with significant equity.
Direct influence over product and company direction from day one.
Work alongside experienced founders in a high-ownership, high-impact environment.
Note: Visa sponsorship is not available for this role.
Location
This role is on-site in London, United Kingdom. You'll be working closely with the founding team in person.
Clera is building autonomous AI agents that handle end-to-end recruiting operations. The company's AI agents find candidates, write personalized outreach, handle conversations, qualify fit, and schedule interviews without human intervention. Clera has raised pre-seed funding from top investors and has grown to marketplace scale with 40,000+ talents and hundreds of top startup customers. The company is now scaling its AI-native recruiting platform by hiring operators who supervise the agents, handle high-judgment moments, and close candidates that require human touch.
