Applied AI Engineer (Junior - Middle, English)

Build like a founder. Ship like Spartan.Our customers are scaling fast and so are we. That’s why we’re looking for an Applied AI Engineer to join our world-class team.At Spartan, we don’t act like contractors. We embed with startups backed by YC, Pear VC, BlingCap, a16z, Techstars, and more - partnering with founders and engineers from Stanford, MIT, Yale, Google, Amazon, Uber, and beyond. Together, we help launch MVPs in 30 days and scale systems that power billions of requests.This isn’t “just another AI role.” It’s a chance to work shoulder-to-shoulder with elite builders, solve complex startup challenges, and see your work directly drive companies raising millions on the global stage. You’ll also be at the frontier of AI: 70% of our portfolio is LLM-powered. Key ResponsibilitiesPrompts & Interfaces: Design clear prompt templates and role scaffolds (System/User/Assistant). Prefer structured outputs (JSON/schema).Context & Memory: Keep chats relevant with windowing/summarization and retrieval-backed long-term memory; basic tenant/privacy scoping.RAG Pipeline: Chunk/clean docs, embed into a vector store, run hybrid retrieval (BM25 + dense), and return answers with citations.Grounded Answers: Favor evidence, cite sources, and abstain when unsure.Agent Loops & Tool Use: Implement Plan → Act → Observe → Iterate; call APIs/DBs via typed tool contracts.