Software Engineer ($150k-$250k + Equity) at Greylock-backed AI startup for physical sciences

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 Software Engineer Salary $150k-$250k + Equity Company Description Greylock-backed seed startup building the AI intelligence layer for physical sciences Job Description Join a high-caliber founding team of ex-SpaceX and Warp engineers to architect a scientific intelligence platform. You will build systems that ingest and reason across multimodal R&D data—spreadsheets, technical documents, and lab notebooks—to accelerate breakthroughs in semiconductors and aerospace. This is a rare opportunity to define the technical foundations of a category-defining AI company. Location San Francisco, USA Why this role is remarkable Work at the intersection of AI and physical science alongside a world-class team from SpaceX, Warp, and Jane Street. Backed by elite investors including Greylock, Neo, BoxGroup, and angels like Jeff Dean and leadership from OpenAI and AMD. Massive impact potential by replacing outdated legacy software with an intelligence layer for industries representing trillions in R&D spend. What You Will Do Architect and build the early foundations of the core product and data ingestion infrastructure from scratch. Develop LLM-based agentic systems and custom AI implementations to extract insights from messy, multimodal scientific data. Ship end-to-end features as a technical leader, influencing the long-term engineering culture and product vision. The ideal candidate Proven track record of shipping 0-to-1 products in fast-paced environments like early-stage startups or applied AI labs. Deep technical experience building production-grade LLM applications, agentic workflows, or complex ML infrastructure. Product-first mindset with a bias toward action and the ability to work in-person 5 days a week in San Francisco. 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.