Lead AI Engineer ($175k-$275k + Equity) at Terranox AI

This is a job that Jill, our AI Recruiter, is recruiting for on behalf of one of our customers. She will pick the best candidates from Jack's network. The next step is to speak to Jack. Job Title Lead AI Engineer Salary $175k-$275k + Equity Company Description Terranox AI (YC W26) is an AI-powered uranium discovery company using physics-informed machine learning and frontier models to modernize mineral exploration. Backed by founders with NASA and geophysics PhD backgrounds, they integrate deep domain expertise with advanced AI to secure the future of energy production. Job Description You will lead the design and development of core AI systems at Terranox AI, turning complex geoscience data into trusted discovery pipelines. Working with a small, high-velocity team, you’ll build multi-agent reasoning systems and rigorous evaluation frameworks that directly inform drilling decisions for critical uranium deposits across North America. Location San Francisco, USA Why this role is remarkable This is a high-ownership role where your AI systems directly dictate multi-million dollar drilling decisions and the discovery of critical energy resources. You will work at the intersection of frontier LLMs and physical science, solving unique technical challenges like retrieval over heterogeneous, decades-old scientific corpora. Join a YC-backed team led by a geophysics PhD and a former NASA JPL engineer, positioning you at the forefront of the AI-driven energy transition. What You Will Do Design and ship production-grade multi-step reasoning pipelines and multi-agent systems using frontier models and tool-use orchestration. Build and optimize complex retrieval systems capable of indexing and reasoning over large, messy, and heterogeneous scientific data sources. Develop rigorous LLM-as-judge evaluation frameworks to ensure model reliability where ground truth is difficult to obtain. The ideal candidate Has 4+ years of software engineering experience with at least 2 years specifically building and scaling production-level LLM systems. Demonstrates deep expertise in Python and SQL, with a proven track record of designing large-scale data and agent-based pipelines. Possesses the ability to collaborate with non-engineering domain experts, such as geologists, to frame and solve highly ambiguous technical problems. Who are Jack & Jill? Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support. And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate. How does this work? Jack's an AI agent for job searching and career coaching. He works for you. Jill is the AI recruiter working for the company. She recruits from Jack's network. If it's a match and the company wants to meet you, they'll make the intro. In the meantime, if you'd like, Jack will send you excellent alternatives. 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. Show more Show less