General Partner @YCombinator, Co-Founder @FutureAdvisor (YC S10), MIT EECS

Joined June 2007
63 Photos and videos
May 31
Your startup's growth rate is also its learning rate. Setting an ambitious growth goal and trying to hit it is the fastest way to find out what's broken and how to fix it. Not just the obvious stuff. Wrong customer, wrong problem, product nobody wants. It also stresses the founding team. You find out fast whether you can handle hard problems under pressure. Bottlenecks only show up when you push. If you're not having uncomfortable discoveries early, you're not pushing hard enough.
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Replying to @charliermarsh
Sometimes they're a good reason to work on something. When people say a market is "crowded," what that often means is that there's a real problem and none of the solutions are good enough yet.
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May 24
Founders often ask me what to listen for in customer calls to know if they have a hair-on-fire problem. This is the wrong question. Can you run their business? If you were CEO, would this be a top 2 priority? Because most businesses never get to #3. Rather than pitching your idea, learn the business so well you could run it yourself. You'll know exactly how big the problem is and what they'd pay. And if this is going to 100x their business and they still won't buy? You just discovered the AI version of their company.
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A mic drop moment @ycombinator tonight @sama just offered $2M in OpenAI tokens to EVERY YC startup in the current batch in exchange for equity Just like Yuri Milner offering to invest in every startup back when Sam was a YC partner I can't wait to see what's unlocked when you let the most driven, creative and formidable founders tokenmaxx
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May 4
The YC application deadline is today. If you're working with AI to close the scientific discovery loop, drop an application and tell us about it.
Replying to @sdianahu @agupta
AI-Native Discovery Engines @xuster For centuries, scientific discovery has run on the same loop: hypothesize, experiment, interpret, repeat. It works, but it's slow. Frontier models have now reached PhD-level performance on scientific reasoning, and the frontier is shifting from copilots to systems that can run closed discovery loops on their own.
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We’re bringing Jensen Huang to Startup School for a fireside chat with @garrytan! From co-founding @nvidia in 1993 to building the backbone of the AI era, Jensen helped turn GPUs into the engine of modern computing. Apply to attend: events.ycombinator.com/start…
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This summer we're launching YC Paper Club to bring researchers & builders together. Every few weeks we'll host a small group dinner in Mountain View to share and discuss new research papers. Interested in both research & building the future? Sign up at: events.ycombinator.com/ycpap…
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MIT student asked a question earlier today that a lot of young founders are quietly wondering about: "Won’t the frontier labs just do everything?" Yes it's true that OAI/Ant are shipping at incredible pace, but it's quite easy to avoid their blast radius and build amazing startups: OpenAI is not going to build a cattle-herding drone, buy an old F-150 and drive from ranch to ranch like the founder of one of the fastest-growing YC W26 startups, Graze Mate. Anthropic is not going to integrate with dental insurance verification systems (Lance). Google is not going to navigate NATO procurement (Milliray). The value is in the last mile, not the model. Sales cycles require humans who understand the customer. And most importantly, the market is expanding, not shrinking: AI isn't cannibalizing the existing 1% software spend — it's unlocking the other 5-6% that was going to humans. That's a much bigger market for startups yet-to-be-founded than the one the labs are playing in. Now, what DOES seem risky? A thin UI layer on top of ChatGPT with no domain expertise; a general-purpose chatbot or assistant; or a product that gets obsolete when model capabilities improve. But — tools for specific industries; "full-stack" AI companies that actually are the service (AI law firm, AI accounting firm, AI uranium exploration company); or generally products where the customer doesn't want a tool but an outcome — are defensible ideas for startups.
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Grateful to have @demishassabis and @GoogleDeepMind stop by YC today and hang with founders!
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Congrats to @astorinvest on their $5M seed! They're building an AI investment advisor for everyday investors. It connects to your brokerage, analyzes your portfolio, and delivers personalized recommendations. Less than two months after launch, thousands of users have already connected over $200M in assets to the platform. fortune.com/2026/04/23/jjjj/
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AI isn't just making teams more productive. It's changing how companies should be built. In this episode of Startup School, YC Partner @sdianahu explains what it means to build an AI-native company, where AI isn't just a tool but the operating system your company runs on. She breaks down how to make your company queryable so agents can improve across every function, why management hierarchies break down when an intelligence layer replaces human middleware, and why early-stage founders have a massive edge in building this way from day one. 00:58 - AI as your company’s operating system 01:57 - Open vs closed loop companies 03:00 - Making your company fully queryable 05:00 - The rise of the 1,000x engineer 07:12 - Why middle management disappears 09:12 - Startups will win this shift
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Apr 23
Everyone thinks about money differently. The last generation of personal investment software was fine but not truly optimal for anyone. I know because I built one. AI unlocks a truly personalized advisor with deep understanding of financial situations and personal opinions. Excited that @brunokoba_ and @tulha_ are building this at @astorinvest. Congrats guys!
We (@astorinvest) raised a $5M seed led by Monashees, with participation from Goodwater, Gilgamesh Ventures, and other incredible investors. In less than two months after launch, thousands of users have connected over $200M in assets to our platform. We're just getting started.
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Apr 22
The team at @10x_Science is delivering a huge unlock for drug development by increasing the speed of protein characterization by orders of magnitude. David, Andrew and Vishnu are an insanely talented team working on a huge problem! And they’re hiring.
Congrats to @10x_Science on their $4.8M seed! They're building AI for molecular-level protein characterization, a process that today requires specialized scientists spending weeks or months manually interpreting complex data. Their platform delivers the same insights in minutes. techcrunch.com/2026/04/22/ai…
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Apr 18
That’s a wrap on YC Startup School India. Bengaluru, you really brought it. We can’t wait to see what you’re going to build.
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📍 YC startup school
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YC startup school india avengers moment
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Apr 18
Insane builder energy. Let’s go Startup School India!
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Apr 18
What an epic lineup of founders for Startup School India. Looking forward to our conversations with them!
Grateful to these incredible founders for speaking at Startup School India today. Aadit Palicha (Zepto) Harshil Mathur (Razorpay) Vidit Aatrey (Meesho) Lalit Keshre (Groww) Mukund Jha (Emergent) Varun Vummadi (GigaML) Six YC-backed Indian founders. Combined company value: $25B . Jobs created in India: over 250K.
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Grateful to these incredible founders for speaking at Startup School India today. Aadit Palicha (Zepto) Harshil Mathur (Razorpay) Vidit Aatrey (Meesho) Lalit Keshre (Groww) Mukund Jha (Emergent) Varun Vummadi (GigaML) Six YC-backed Indian founders. Combined company value: $25B . Jobs created in India: over 250K.
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We had room for 2,000 people at Startup School India. More than 25,000 applied. No Startup School anywhere in the world has ever had this many people apply. Not SF, not NYC, not London. India blew them all away.
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