YC and Together AI are partnering to bring the first dedicated YC GPU cluster online, giving YC startups easier access to the compute they need to build and scale. In this Founder Fireside, YC's @agupta and @togethercompute co-founder & CEO @vipulved dig into why compute has become one of the biggest bottlenecks for modern AI companies, how Together AI is helping more than 8,000 customers—from early-stage research teams to companies like Cursor, Cognition, and ElevenLabs—train, fine-tune, and serve AI models, and why flexible access to GPUs is becoming a competitive advantage for the next generation of founders. 00:00 — Partnering on a GPU Cluster 00:26 — What Together AI Does 01:22 — From Research Labs to Cursor: Together's 8,000 Customers 01:58 — The Landscape of AI Native Startups 03:24 — How Building an AI Company Has Changed Since 2018 04:56 — Why the Cost of Compute Keeps Going Up 05:29 — YC as the Biggest Seed Funder of Research Companies 08:47 — Flash Attention, Mamba, and the Science of Production AI 10:43 — Compute Planning Advice for Early Stage Companies 12:39 — When Your Compute Bill Is Bigger Than Your Cash Balance 13:31 — How Companies Are Using the Cluster Today 14:24 — What's Next