Senior Backend Engineer

Senior Backend Engineer | London | AI x 0→1 Product | Python | Competitive Salary + Equity We’re working with a $9M-backed AI company building a new product that helps people manage their travel, dining, experiences and other personal requests through AI. Early stage so you’ll be building the product from scratch, working directly with the CTO and founders. You’ll be working mainly in Python, building backend services, APIs, data pipelines and AI features, and taking what you build into production. No legacy systems, no internal CRM and no endless ticket queue. You’ll have real ownership over what gets built. What you will be doing Architect and build the backend from the ground up you'll have a genuine say in how the system is designedTake ideas from 0→1, through architecture, implementation, deployment and iterationBuild high-performance APIs, background workers, data pipelines and third-party integrationsDesign and ship AI agent workflows, including LLM orchestration, tool calling and retrievalSolve problems around latency, reliability, observability, cost and model performanceMake the difficult calls around architecture, infrastructure and technical trade-offsWork directly with the CTO and founders no six layers between you and the decisionShip to real users, learn from what breaks, and improve it What I'm Looking For Excellent software engineering fundamentals CS fundamentals actually matter hereStrong production experience with PythonStrong backend/API engineering experienceExperience building and shipping 0→1 products or significant greenfield systemsStrong understanding of distributed systems, databases, concurrency and asynchronous processingHands-on experience with LLMs, AI agents, RAG, embeddings or model-driven applicationsSomeone who can look at an ambiguous problem and work out the architecture rather than waiting for someone else to define itA track record of shipping GitHub, products, side projects, startups, whatever proves you build Tech Stack FastAPI / DjangoPostgreSQLAWSRedis / Celery / KafkaVector databasesAgent orchestration / tool callingRAG / retrieval systemsLLM evaluation and observabilityAI-native productsHigh-growth startupsStrong open-source projects Top university / Computer Science background is highly valued, particularly from places such as Imperial, Cambridge, Oxford, UCL, Edinburgh or Warwick but I'm much more interested in what you've actually built than a university name on a CV. Why this one is different You won't be joining a huge engineering organization and owning 3% of a service nobody understands. You'll be one of the engineers actually building the thing. You'll have direct access to the people making the decisions, meaningful equity, serious technical ownership and the opportunity to put your fingerprints on the architecture before it becomes difficult to change. If you're the type of engineer who sees 0→1, greenfield, AI agents and “figure it out” and thinks that's exactly what I want to be doing! I'd like to hear from you Apply with your CV.