Founding Engineer ($170k-$350k + Equity) at well-funded AI infrastructure startup

Job Title: Founding Engineer Salary: $170k-$350k + Equity Company Description: well-funded AI infrastructure startup Job Description: You will build the simulation and evaluation infrastructure that powers the training of frontier AI agents. By developing containerized sandboxes and orchestration systems, you will enable research labs to improve agentic models through rigorous simulation. This role offers the rare chance to work on the infrastructure layer of LLM-based agent self-improvement. Location: San Francisco, USA Why this role is remarkable: Work at the frontier of AI infrastructure, building the simulation environments used by leading research labs to train and reward next-generation agents. Join an elite founding team with deep experience scaling simulation systems at world-class autonomous vehicle and aerospace companies. Massive technical ownership in a low-ego environment where you will influence the core product architecture and ship code daily. What you will do: Design and scale distributed backend systems, including containerized simulation sandboxes and high-throughput orchestration pipelines. Build robust grading and evaluation infrastructure to provide the reward signals necessary for RL-based agent training. Collaborate directly with AI researchers to translate complex agentic workflows into reliable, production-grade infrastructure. The ideal candidate: Proven track record of building complex distributed systems, ML pipelines, or platform infrastructure at high-growth, technically ambitious companies. Strong systems thinking and fundamentals in distributed systems, with the ability to move quickly across a full-stack TypeScript and Kubernetes environment. Founder mentality with an obsession for shipping fast, navigating ambiguity independently, and maintaining high technical standards. Next steps: Visit our website. Click "Talk to Jack". Talk to Jack so he can understand your experience and ambitions. Jack will make sure Jill (the AI agent working for the company) considers you for this role. If Jill thinks you're a great fit and her client wants to meet you, they will make the introduction. If not, Jack will find you excellent alternatives. All for free. We never post fake jobs: This isn't a trick. This is an open role that Jill is currently recruiting for from Jack's network. Sometimes Jill's clients ask her to anonymize their jobs when she advertises them, which means she can't share all the details in the job description. We appreciate this can make them look a bit suspect, but there isn't much we can do about it. Give Jack a spin! You could land this role. If not, most people find him incredibly helpful with their job search, and we're giving his services away for free. #J-18808-Ljbffr Jack & Jill/External ATS