Software Engineer

About Us: Composo is on a mission to ensure that AI transforms our world effectively, rapidly, and safely. Our platform helps customers squash the legal and reputational risk associated with shipping AI apps and improves the helpfulness of our customer’s AI agents. We believe subject matter experts are critical to evaluating and improving AI applications. Our platform equips them a powerful evaluation toolkit in a no-code interface, while giving engineers the development freedom they need to ship their best code. We’ve raised £1m from top angels and VCs (ex-unicorn founders, head of AI at Novartis, etc) As we continue to grow, we are looking for an exceptional Founding Engineer as our first engineering hire. What You’ll Do Shape the architecture and lead technical decisions that will form the foundation of our product Develop full-stack features, balancing rapid iteration with maintainable code Design intuitive UX flows and collaborate on product vision with the founding team Manage DevOps, ensuring robust CI/CD pipelines and system reliability Engage directly with customers, gathering feedback to drive product improvements About you You have 3 years of experience in backend or full-stack development and are proficient in Python and relational databases. Shipping production code is what you do best. You’re a first principles thinker, capable of both running autonomously and collaborating closely. You’re comfortable with the uncertainty and highs and lows of a pre-revenue startup. Willingness to be on-call for production support on a rotational basis. You’re excited about collaborating with our London team in person. Nice to haves: Experience with out backend stack: FastAPI & Postgres Experience with or interest in SDK design and Developer Experience. Experience architecting scalable cloud infrastructure. ML/AI experience. Experience working in early stage startups. Our Stack: We use Python & FastAPI for our backend with a Postgres db. Our frontend is React Typescript with DaisyUI for components and Tailwind for styling. Our ML leans heavily on OpenAI and the Huggingface/Pytorch stack. We’re hosted in MS Azure. What We Offer: Opportunity to work on the biggest blocker of global AI adoption today. Small team of highly motivated, independent and intelligent people. Competitive salary and equity. Massive learning opportunity and a high degree of autonomy. Explosive career growth by getting in early at a fast growing startup. Location: Waterhouse Square, London