Y Combinator Startup Podcast

Stoke Space is racing to build the world's first fully reusable rockets that can launch, survive reentry, and fly again and again. In this episode of Hard Tech, YC’s Aaron Epstein sits down with Stoke Space co-founders Andy Lapsa and Tom Feldman to find out why they chose to take on one of the hardest problems in rocket science, how an obsession with efficiency gives them an edge, and what full reusability could unlock for the future of spaceflight.Apply to Y Combinator: https://www.ycombinator.com/applyWork at a startup: https://www.ycombinator.com/jobs

2025 was the year AI stopped feeling chaotic and started feeling buildable. In this Lightcone episode, the YC partners break down the surprises of the year, from shifting model dominance to why the real opportunity is moving back to the application layer, and why the next wave of AI startups may be just getting started.

ARC-AGI is redefining how to measure progress on the path to AGI - focusing on reasoning, generalization, and adaptability instead of memorization or scale.During this month's NeurIPS 2025 conference, YC's Diana Hu sat down with ARC Prize Foundation President Greg Kamradt to find out why most AI benchmarks fail, how ARC-AGI reveals the limits of today’s models, and why measuring intelligence may be harder than building it.

Head of Design Ryo Lu helped transform Cursor from a feature-layer on top of VS Code into one of the world's leading AI code editors.He joins YC's Aaron Epstein on Design Review to talk about the path that brought him to Cursor, how rapid prototyping reshaped the core product and how he's breaking down the barriers that once separated designers and coders.

In just a few years, James Hawkins took PostHog from an idea hacked together right before YC's W20 deadline to a unicorn powering product analytics for thousands of teams.He joins YC's Brad Flora to talk about surviving six months of "pivot hell," why open-source analytics was the breakthrough, and how PostHog grew from fighting for its first users to launching full product lines—plus what he's learned about momentum, staying close to customers, and using transparency and humor to build a company that stands out.