Managing Partner of Pioneer Fund. We are 500+ Y Combinator alumni investing in the top YC startups. YC S11.

San Francisco, CA
Joined June 2015
I LOVE when two @pioneer_fund portfolio companies work together. Congratulations @theoremlabs on this important work with @AnthropicAI!
New on our Frontier Red Team blog: using Claude to formally verify software at large scale. Formal verification can prove that code is free of certain bugs, but historically it has only been feasible for small codebases (or required a lot of expert time). With AI models, however, this is beginning to change. In collaboration with @theoremlabs, we used Claude to prove security properties in over one hundred real-world open-source libraries over the span of a few weeks. Read our research in full here: anthropic.com/research/forma…
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The feeling of everything being insecure and under attack is not pleasant. Like walking through a war torn area or very high crime area. You can sort of protect yourself but only to an extent and only with extreme vigilance.
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1 new user per minute... for 8 hours straight I've never been happier to have spent my weekend load testing the hell out of our infra lmao We're doing NUMBERS Sign up before 9 AM PT tomorrow and get 50,000 requests on us :)
We raised $9M to give your agents the internet. Led by @generalcatalyst, with @orangecollectv and Robinhood Ventures. Search, scrape, crawl, monitor with one API trusted by 800+ customers. We’re making it ridiculously easy to build with web data.
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X needs <spoiler> tags. @nikitabier I feel like if you were still there, you could get this done in 5 mins. 10/10 though as a longtime Nathan Fielder fan.
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Tim Suzman retweeted
10x a year for 3 years? I've seen a lot of growth, and that is truly exceptional. It's not unusual for startups to grow 10x in a year, but to keep it up for 3 years is close to unheard of. That's 1000x.
Exa just passed $100m in annualized revenue. We've grown almost exactly 10x per year for 3 years. We now handle 2 billion requests a month from 200k+ teams. And it’s still so early: We predict agents will search 1000x more than humans by 2030. Agents don't search like humans. They write long, complex queries and want all the world's data, not just the web. We've spent 5 years building a search engine designed for them. We now serve personal agents, AI labs, coding agents, GTM agents, really any agent. Exa gives these agents access to 100s of billions of web documents and tons of proprietary data. Our customers are increasingly noticing that information is the bottleneck to agent performance. While the world seems close to perfect intelligence with models like Fable and Astra, we are very far from perfect information. To our small but legendary team, thank you for getting us here, from engineering to research to GTM to ops. To our customers, it is an honor to serve you. We have some exciting releases coming soon and can't wait to share them 🫡
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From my opinion when we first invested in Exa in 2021, pre revenue.
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This is insane. Exa grew 10x to $100M in revenue. svpost.com/articles/exa-100m…
Exa just passed $100m in annualized revenue. We've grown almost exactly 10x per year for 3 years. We now handle 2 billion requests a month from 200k+ teams. And it’s still so early: We predict agents will search 1000x more than humans by 2030. Agents don't search like humans. They write long, complex queries and want all the world's data, not just the web. We've spent 5 years building a search engine designed for them. We now serve personal agents, AI labs, coding agents, GTM agents, really any agent. Exa gives these agents access to 100s of billions of web documents and tons of proprietary data. Our customers are increasingly noticing that information is the bottleneck to agent performance. While the world seems close to perfect intelligence with models like Fable and Astra, we are very far from perfect information. To our small but legendary team, thank you for getting us here, from engineering to research to GTM to ops. To our customers, it is an honor to serve you. We have some exciting releases coming soon and can't wait to share them 🫡
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This Opus 5.5 trend is fun. 🔉
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Made in JavaScript
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Most of the replies are saying this is ok/normal behavior. They are all wrong. I’ve made over 1,000 investments and this behavior is totally unacceptable.
Someone introduced me to an investor that they thought I would connect with. After the meeting and the investor was really intersted, the person that connected us called me and said he wants 5% of the raise as an intro fee. That's insane, right?
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I’ve watching this 100+ times. I don’t usually look backwards. I’m wired to be always racing forwards, driving to the next goal, never moving fast enough. But first flight was special. The result of years of work with the greatest team I’ve ever had the privilege of working with. This was a day, and an accomplishment, worth reliving again and again.
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I am feeling the opposite effect from having agents. Overwhelmed by opportunity. I wish I could work 3 days per day.
I am most afraid of us eating the productivity gains of agents by just becoming lazier.
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My 7-year-old added 3 new levels to his game. Without any help from me, using Claude Code. wallbreakergame.com 🔉 Sound on - all the sound effects are his own voice recordings. Last time he was really excited to see people playing from 20+ countries. If you play from somewhere cool, comment below!
My 5-year-old (now 6) made a computer game. Wallbreaker. The night before, he dreamed the whole game. He used cursor (this was back with Sonnet 3.5) and dictated to me since he didn't know how to spell yet back then. He built the first level in one day. "Last night I dreamed I made a game. And today I’m playing my dream." All the sound effects he voice-recorded into my iPhone. wallbreakergame.com/
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My all-time best investments felt both heart-pounding and uncomfortable.
Investing often means feeling uncomfortable, or sometimes even wrong, for long periods of time. When you say no to the investment everyone else is doing, or make the investment no one else wanted to touch, it's almost impossible not to question yourself. But when you're ultimately right, there's no better feeling.
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h/acc - accelerate humanity
Be careful what you wish for This is why we need alignment to humankind vs any other goal
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For the last few years I've wanted someone to build a time machine for the internet. I'm glad it's a portco! Nice going @ExaAILabs. This will be critical infrastructure for AI.
We built a time machine for the web. Introducing Exa Snapshot: an index of 400 billion historical snapshots of webpages that lets you search as if it's the past. Snapshot is already being used for backtesting prediction models, RL at labs, exploring the pre-AI web, and more.
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When I was 13, I beat Chessmaster 4000. I remember printing this certificate and storing it, so that one day, I could show my kids. So they could see it was once possible to defeat the computer at chess.
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