At a Glance
- Tasks: Architect systems to transform complex energy documents into actionable AI data.
- Company: Join cepter, a pioneering AI infrastructure startup in London.
- Benefits: Equity options and the chance to shape the future of energy tech.
- Other info: Dynamic, high-intensity environment with rapid shipping and cutting-edge tools.
- Why this job: Be the first engineer and directly influence product architecture and company culture.
- Qualifications: 6+ years in high-performance startups with expertise in Python/FastAPI and TypeScript/React.
The predicted salary is between 60000 - 80000 £ per year.
cepter is a London-based AI infrastructure startup building the platform to unlock proprietary energy sector data for the AI era. Founded by Kaspar (ex-BCG/terralayr) and Duxi (ex-IBM/ETH Zurich), they are transforming complex technical reports and legal contracts into machine-ready data to accelerate the global energy transition.
As the first engineering hire at cepter, you will architect the systems turning complex energy documents into actionable AI data. You'll build end-to-end features using FastAPI, React, and Temporal, owning everything from database migrations to LLM pipelines. This high-intensity role offers the chance to define the technical foundation for the energy transition’s AI infrastructure.
Location: London, UK
Why this role is remarkable:
- Shape a company from day one as the first engineer, working directly with founders from Oxford, BCG, and ETH Zurich to define the product architecture and culture.
- Solve critical data bottlenecks in the energy transition by building sophisticated AI pipelines that process high-stakes proprietary documents and complex legal technicalities.
- Join a high-performance, high-intensity culture designed for rapid shipping, utilizing cutting-edge tools like Temporal for workflow orchestration and AI-native development workflows with Cursor and Claude.
What You Will Do:
- Ship end-to-end features across a FastAPI and React/TypeScript stack, designing durable domain APIs and data models that work in production-like PR previews.
- Build and debug complex Temporal workflows for long-running AI pipelines, ensuring idempotency, retries, and reliable structured extraction from unstructured documents.
- Own the entire infrastructure and DevOps lifecycle using Docker Compose and Railway, while improving developer experience through robust CI checks and observability.
The Ideal Candidate:
- Brings at least 6 years of experience at high-performance tech startups with a proven track record of shipping full-stack products from scratch.
- Demonstrates deep expertise in Python/FastAPI, TypeScript/React, and building production-grade LLM/document pipelines using tools like Langfuse for quality diagnosis.
- Possesses a “founding bar” mindset: high agency in ambiguity, a bias toward small and correct changes, and comfort pairing with AI coding agents to accelerate delivery.
Founding Engineer (+ Equity) at cepter employer: Jack & Jill
At Jack & Jill, we pride ourselves on being an exceptional employer that fosters a dynamic and innovative work culture. Our team enjoys a range of benefits including flexible working arrangements, professional development opportunities, and a collaborative environment that encourages creativity and growth. Located in a vibrant area, we offer unique advantages such as access to cutting-edge technology and the chance to work with industry leaders in AI-driven marketing strategies.
