Product Engineer

*Y Combinator | Product Engineers | San Francisco (Onsite) | Full-time | https://www.ycombinator.com/software YC is hiring Product Engineers to build the future of YC -- and increasingly, software for startups everywhere. We're a team of ~20 engineers building everything from Work at a Startup and Demo Day to investor software, founder tools, AI systems, and new open source projects. We don't have PMs. Engineers talk to users, decide what to build, and ship quickly. Some of what we've been building: * New products: GStack rethinks the software stack for an AI-native world. GBrain explores persistent memory and knowledge systems for AI. Paxel and other AI-powered products help founders—and increasingly everyone else -- build software and companies faster. * Products at scale: We build and operate Work at a Startup (2M+ candidates, 1000s of early startups), Demo Day, our investor marketplace, SAFE signing, founder CRM, and the software that powers YC itself. * Data: YC has over 20 years of proprietary startup data. We're applying it to how we think about the future of YC's batch, fundraising tools, hiring, recommendations, and entirely new ways to help people start and grow successful companies. AI has fundamentally changed how we build software, and we're looking for engineers who are already experimenting with coding agents, MCP, LLMs, context engineering, evals, developer tooling, and whatever comes next. Our stack includes Rails, React, Postgres, Python, TypeScript, LLM APIs, and plenty of experimental infrastructure, but we're much more interested in great builders than expertise in any particular framework. We're in person in San Francisco (Dogpatch). You'll work closely with founders and alongside people like Garry, Jared and Diana, helping define how YC—and startups more broadly—build software in the AI era. We offer competitive compensation, carry in the YC fund, and a small, high-autonomy engineering team. Learn more about the team and role at https://www.ycombinator.com/software. If this sounds exciting, I'd love to chat -- email me directly at ryan@ycombinator.com.