Y Combinator
YC partners and founders giving early-stage companies direct advice
29:49Robots Learn to Manipulate Using Computer Interaction Data, Not Robot Data
General-purpose large models are bundling programming, computer operation, and spatial reasoning capabilities to robots; the industry expects genuinely general robots—capable of following any instruction and working like a competent teenager—within two years.
36:28Hard Tech Is One-Fifth of the YC Batch: Software Companies Are Being Eaten by Agents
In YC's latest batch, hard tech companies went from 8% to 20%, with robotics, defense, semiconductors and power all doubling or more; meanwhile software companies are shifting from selling tools to selling "getting the work done," and median revenue rose from 8K to 20K.
12:41Outbound Reply Rates Near Zero? Don't Blame the Copy First — Check Who You're Sending To
Outbound is like finding a needle in a haystack: get the person wrong and even perfect copy won't land. The YC partner's debugging order is — check the recipient first, then the company, then the subject line, and only then the copy.
57:15Enterprises will run 80% of tokens through open models, but spend only 20% of budget
Open models and closed frontier models are not substitutes: the vast majority of tokens will run through open models, the hardest work stays with the frontier labs, and routing and orchestration connect the two in between.
14:48The World's Largest Electric Aircraft Just Flew: $5 of Electricity, Taking On Regional Aviation
Heart Aerospace's ES-30 electric aircraft takes off on $5 of electricity, with operating costs 48% lower than the old planes it replaces, targeting half of the world's flights under two hours and using hybrid power to solve the backup battery problem.
21:25What Drives Founders Isn't Becoming a Billionaire, It's the Fear of the Server Crashing at 3 A.M.
Most people assume it's wealth ambition that carries founders through. Paul Graham says what actually pushes people forward day to day is disaster fear — the server goes down, the model train is about to fall off the table; you keep your head down for ten years, look up, do the math, and realize that at the last round's valuation you're already a billionaire.
51:44Mac Icons Aren't About Pixels, They're About Metaphor
Draw less, and users can put themselves into the icon. The 16×16 black-and-white constraint isn't a design flaw—it's the constraint that forces good ideas.
58:17A single robot model matches fine-tuned specialists out of the box
One robot model now matches task-tuned specialists zero-shot, and above all composes learned skills onto robot arms it has never seen — all of it resting on using prompts to tame low-quality, heterogeneous data. The bottleneck is shifting to reliability, speed and physical distribution.
57:02Deep Tech Companies Lose to Their Org Systems, Not to Technical Failure
How fast a startup can iterate decides how long it can win; and iteration speed comes from "infrastructure" like procurement, hiring and performance review. Putting approvals at the budget layer and replacing reviews with eigenreviews is worth more investment than agonizing over the specific technology.