Junior AI Developer

We're Hiring: Junior AI Developer Build Halt is a team operations management app that helps businesses organize tasks, connect teams, and monitor work in real time. The platform is designed for industries with field-based teams, such as construction, maintenance, inspections, and facilities management. By simplifying workflows and improving accountability, Build Halt enables organizations to coordinate work more efficiently and deliver better results. You don't need years on your CV — but you should have built something real. If you've put a project in front of users, contributed to a codebase, or gone deeper than tutorials and demos, we want to hear from you. What you'll do * Work on real AI features end to end — prompting, retrieval, evaluation and deployment — with support and mentorship along the way * Turn product ideas into working solutions, learning how to make them reliable as you go * Help maintain the quality bar through testing and monitoring * Work closely with the founders and a small team, with short feedback loops and plenty of room to learn What we're looking for * Around 1–3 years of software engineering experience, or strong personal/academic projects that show it * Solid Python fundamentals and a genuine interest in APIs and cloud infrastructure * Some hands-on exposure to LLMs — even from side projects, internships or coursework * Basic understanding of how LLMs work — prompting, tokens, context windows, and why models sometimes get things wrong * Familiarity with prompt design and a willingness to test, tweak and improve prompts * Exposure to RAG, embeddings or vector databases (Pinecone, Chroma, FAISS, pgvector) * Curiosity about agents and AI frameworks like LangChain or LlamaIndex * Understanding that AI output needs checking — an eye for evaluating quality and spotting when a model is off * Eagerness to learn fast and keep up with a space that changes every week * Right to work in the UK Salary: Negotiable, depending on experience and suitability Location: Central London Nice to have * A project you've built independently and shared with real users * Startup or side-project experience * Curiosity about the AI space and where it's heading Interested? Apply through the link or send me a direct message with a short note about something you've built and shipped — we care more about what you've made than a perfect CV.