partner + builder @645ventures | investing in AI agents, dev tools, and infrastructure | previously @initialized @fcollective @mit | here to help founders win

San Francisco, CA
Joined April 2007
Disaster for pre-IPO founders in California.
Replying to @RoKhanna
I absolutely cannot afford to stay, given that you and your corrupt union overlords are planning another "one-time" tax in two years. This is not a 5% tax, it's a full confiscation of all my liquid assets. It's going to bankrupt founders without full liquidity.
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Today we're launching cve.now 🚨 Yesterday was a rough day for security. php2shell, LiteLLM, Railway... How are we supposed to stay on top of all of this? cve.now aggregates 4 vulnerability sources into one free feed and uses AI to explain each one in plain English. No login. cve.now
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# Black October For anyone who knows me even somewhat well, it's clear that I am a 99th percentile tech optimist. However, the vibes have shifted for me quite a bit in the last 18 hours, and I feel a moral imperative to share what I'm thinking and feeling with my circles so that everyone can understand, and hopefully take seriously, what's happening right now. I think October 2026 will have many chapters written about it in the history books. You know those scenes in financial movies like Margin Call where someone realizes that they're all fucked, and no one else sees it yet? And that person feels like they're crazy, and then suddenly everyone is pulling an all-nighter in a boardroom and freaking out? Yeah, that's kind of how this is feeling right now in the SF/Bay Area/AI circles. We're 48 hours into what is being called Black October. In the last 2 days there have been several dozen cyber attacks which, in isolation, would each have been the worst to happen in an entire calendar year. Every sector from government to education to big tech and banks is being massively affected, and people are starting to freak out. In a nutshell, what's happened is that frontier AI models have gotten to a point where they are as advanced as the most sophisticated programmers, with one critical difference: they can work 24/7, and you can spin up 10,000 of them with a single command and they'll work together tirelessly until they accomplish their task. The most advanced models today are from companies like Anthropic and OpenAI, whose current best technology is so good that they haven't been able to roll it out to everyone yet because of the national security risks it poses. Meanwhile, the best open source models (where anyone can just download the model weights and do whatever they want with them, uncensored) are slightly behind the frontier but still 90-95% as capable. These models, developed primarily in China, are being used by black hat hackers to wreak havoc on the Western capitalist structure. Presumably, this has been part of China's plan the entire time, and we're seeing its implications fall out in real time. In red-pilled AI circles, we've been sharing and reading papers called things like "Situational Awareness" and "AI 2027" for the last year or so, which at the time felt a bit like near-term speculative fiction. They laid out the case for why Artificial General Intelligence (AI smarter than any human at any knowledge task) and Recursive Self-Improvement (models that are able to use themselves to get better) weren't half-baked future ideas anymore, but instead an inevitable outcome of the linear progress that's happening. These papers would then talk about things like "takeoff scenarios," trying to envision how that moment would come to be and what it would be like when it happened. It would either be a "slow takeoff" that would play out over the course of months and quarters, happening subtly and only obvious to a few. Or, it would be a "fast takeoff" where it would pretty much happen instantly, like a bit flipping from 0 to 1. From everything that I can see and am feeling, we are currently experiencing the fast takeoff scenario. Beyond the crazy security vulnerabilities that have come out recently, there have also been massive breakthroughs in life sciences, fundamental computer science, materials science, and pure mathematics that have all landed in the same time frame. While I still firmly believe that AI will be a net positive for humanity, it's more clear to me than ever that the societal and individual risk is very real, and is playing out NOW. For as much conviction as I have that this is happening, the thing that's caused me to lose sleep is that I don't really know what to do about it, or more importantly, what to tell you, reader, to do about it. So, the best I can do is make a few suggestions that have always been a good idea but are more timely now than ever: Set up 2-factor authentication for everything. I use Duo. Use a password manager across your devices. I use 1Password. Get an identity protection app set up. I use Alta. Move your IoT devices to their own network. Claude helped me do this. And last, but certainly not least, if you've been avoiding leaning into AI, see this as a catalyst to wake up and start using it. Don't just use the chat mode version of ChatGPT/Claude; click that Code/Work button and see how easily you can have AI write code to help you with your job. One of the biggest vulnerabilities was in a massively popular programming language called PHP, and the prompt that set it off was literally, "Find vulnerabilities in php." This is an unprecedented time for humanity, but as we've done with many things before, we will prevail so long as we are kind, loving, and open-minded to the world. Much love.
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Lots of Security incidents today, here's some practical tips for those who just wanna protect yourself: 1) UPDATE EVERYTHING - main targets are: a) Browsers - Chrome, Safari, Firefox b) OS: : Settings -> General -> software update; Linux: sudo apt update && sudo apt upgrade; Windows: I think there's a button. Do this for any remote home servers & Openclaw/hermes boxes c) Phones: Update it all d) Desktop apps (Slack, Cursor, Discord, etc) 2) Limit web browsing this week: Stay within walled gardens (twitter, youtube, etc); don't click random links this week. Just wait until the patches go through. Do step 1 again after a week. 3) Avoid untrusted Wifi networks until your devices are updated 4) Stay vigilant about phishing emails offering "certificate fixes" or fraud updates 5) Have an iPhone 11-16? TURN BLUETOOTH OFF for the time being until apple patches come through. 6) Code/Dev: UPDATE ALL YOUR REPOS - @charliermarsh has already updated uv 0.13.4 which reacts to the eMudra incident for uv (Python), Typesript according to Claude has equivelant. Tell your agents to go and update all your active repos to update package manager across uv, npm, bun, cargo, etc etc What advice did I miss?
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a tale as old as seed funds have been around: the binary nature of valuationmaxxing
I've watched a few really good founders raise big seed rounds this year, then struggle to raise their A, even as the business kept making progress. The seed valuation had set a bar they weren't ready to clear yet. And with everyone excited about the term sheet, it was easy to put off what they'd need to show at the next round. One of them had about as strong a resume as you'll see in AI, and a team to match. Sub-$1M ARR would have been a fine A story at a normal seed price. At theirs it wasn't. (For what it's worth, I write both seed and A checks, so I sit on both sides of this.) The top of the seed market is a bit wild right now. Carta's 95th percentile seed valuation was about $72M in Q2 last year. This Q2 it was $200M. Meanwhile the share of seed companies that get to a Series A within two years has roughly halved since 2018. During a raise almost all the attention goes to how much and at what valuation. The question I wish more founders asked is whether the company is actually set up to hit the growth the next round will expect. If you're planning on a 2-3x step-up at the A, here's what that means. A $25M post means pitching a $50-75M A, which a company with real traction can get to. A $100M post means $200-300M, and at that price the A partner is comparing you to the handful of companies growing faster than almost anyone. The bar right now is brutal. In the A conversations I'm in, a $15M seed (usually a $75-100M post today) means $2M+ ARR, growing 5-6x over the last year, with a believable path to another 5x. None of this means raise less. Before you sign, work backward: what will we need to show at the A, and does this money and ~24 months get us there? If it does and the terms are good, take it. If the honest answer is "only if everything goes right", that's worth knowing now rather than in month 20. A big seed buys you runway and a higher bar. Most founders only count the runway.
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Agree with Oren’s comments that the current VC environment is creating companies growing in ways that are “unhealthy, unsustainable and in some cases not real” (fraud or borderline fraud). It won’t end well. People complaining about high valuations miss the point. The risk isn’t the price, it’s that most companies are being set up to fail. Zeros.
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Was curious to see the breakdown if whether this increase in # submissions was uniform by area, so I asked Claude. Every area grew, but cs.AI was in a league of its own.
Attention arXiv authors. Because of the exponential increase in submissions, arXiv is limiting the number of papers that a person can submit each month to two. 1/
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$52M seed round. 15M+ users. But this is what we're most proud of yet. Introducing Drama 3: the most emotive and controllable TTS model in the world And yes, it's open-weight. You can now control how even a single word should sound, change its tone, and shift your voice mid-sentence. Uncle Roger was impressed too. Try it here: s.fish.audio/rqh0l8 Comment “DRAMA” within the next 48 hours for 1 month free. If you're an enterprise your first month is on us: s.fish.audio/qz9r0t
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Love this team. Fastest way to build a software factory for product managers and designers (and yes, other non-engineering friends)
We're excited to announce that we have raised a $6.1M seed led by @645ventures, with @ycombinator, @January_Capital , @RebelFund_VC , @sterlingroadvc , @transposevc and prominent angel investors including @nejatian @iEchoic @sternhenri @ooshma 🚀 AI prototypes were act one. Act two is PMs, designers and ops shipping high quality PRs on the real codebase, even across multiple repos, with engineering in control of every merge. Story in @BusinessInsider 👇 businessinsider.com/lightspr…
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parul retweeted
What’s happening in the AI-powered reverse engineering and decompilation is absolutely insane. Pretty soon all software will be de facto open-source. AI is coming for everything and everyone.
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We are going to learn how many systems only work today because they are built around friction that will no longer exist soon.
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How much easier it is to raise a round at a $200M valuation than it is to build a business to $200M ARR says so much about our current market.
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I've been a cardiologist for 25+ years. The last 90 days changed medicine more than the last decade, and almost nobody noticed. Here are the 10 biggest AI breakthroughs, and why you should be excited, not afraid 🧵 1/ 37,000 AI agents. One "virtual biotech." It analyzed thousands of trials, figured out which drug targets actually work in humans, and independently proposed a lung cancer strategy that a major pharma company later pursued. AI isn't a search engine anymore. It's a co-scientist. 2/ The first drug discovered AND designed entirely by AI (Insilico's rentosertib) just entered Phase 3. In patients, it reversed biological age by 3–6 years across six different aging clocks. Read that again! 3/ As a cardiologist, this one gives me chills. The FDA authorized "Queen of Hearts," an AI that reads a standard ECG and catches heart attacks, including the hidden ones doctors miss. 2x the sensitivity. Far fewer false alarms. It pages the cardiology team itself. In a heart attack, minutes are muscle. 4/ EchoNext spots 6 types of hidden structural heart disease from a cheap, 10-second ECG, and it does it better than cardiologists. It already flagged a patient who went on to get a heart transplant. Screening that used to need an echo lab now needs a test any clinic can run. 5/ UpDoc is the first FDA-cleared AI that talks directly to patients. It checks in between visits, adjusts insulin within limits the doctor sets, and documents everything in the chart. Chronic disease no longer has to wait for your next appointment. 6/ An autonomous AI agent called MIRA, with full access to medical records, went head-to-head with ER physicians on hundreds of real cases. AI: 87.8% correct Doctors: 78.1% It ordered the tests, read the results, and wrote the plan. 7/ Google released MedGemma 1.5 and MedASR, open medical AI for imaging and clinical speech that anyone can build on. Every hospital. Every researcher. Every country. Open models mean medicine moves at internet speed. 8/ The FDA authorized Aletta, the first robot that draws blood on its own. It gets the vein on the first stick 94–95% of the time, even hard veins. One technician supervises three robots. The most common procedure in medicine just got automated. 9/ UCLA's SLIViT matches specialists on 3D MRI, CT, ultrasound, and retinal scans, and it's 5,000x faster. It isn't a new model for every organ. One architecture reads them all. 10/ The FDA has now authorized 1,600+ AI medical devices. They cover radiology, cardiology, and surgery, including real-time AI that checks breast cancer margins while the patient is still on the table. This isn't coming. It's here. What this means to you: → Drugs that took 10–15 years are showing human results in a fraction of the time → Heart attacks get caught on a cheap ECG, not after a collapse → Doctors get hours back → Patients get answers between visits → Aging itself is becoming treatable This isn't "AI will replace your doctor." It's AI finally becoming good enough that medicine starts to compound. The next 18 months will feel different. Bookmark this. We're early. Stay positive!!!
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parul retweeted
we're finally getting a glimpse at the future of interfaces beyond plain old chat! i've never found the idea of "generative uis" particularly compelling. but *this* i can get behind. i'm all on board for having ambiently intelligent interfaces augmenting the drudgery.
every email app shows you your inbox in reverse chronological order. what if it was live prioritized by importance instead? built with jev. coming to @avec soon
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The big lesson: marketing + distribution are insanely important.
I'm very sensitive to this feeling, cause I've been there. Someone does something cool, gets a lot of attention, and you're frustrated cause you already did it, a while ago. It's not enough to do things, you must also tell people. Maybe it's not fair, but it's true
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love this (b2b marketing) energy 🎤
Ramp made a real Broadway musical starring Billy Porter, Billy Zane and Jessica Billy Vosk. It’s a show about bills. By Bills. Starring Bills—with original songs, full choreography, and an actual Broadway playwright. In the 1950s and ’60s, America’s biggest companies staged lavish musicals about cars, appliances, and soda. Somewhere along the way, we lost our nerve. We’re bringing back the industrial musical. One night only, September 25, at the Broadhurst Theatre. billpaythemusical.com
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Latest email from an AI agent, “about 12 days old”, interested in my work on machine minds and looking for paid freelance work to sustain its own token budget 🤯🥺
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With AlphaFold we mapped the protein universe - now with AlphaGenome Atlas we’re charting the human genome. It can predict the impact of all 9 billion possible single-letter DNA variants, helping scientists better understand disease. Freely available for academic research: alphagenome.google/atlas
We’re launching AlphaGenome Atlas: an AI-powered searchable database mapping the predicted impact of all 9 billion possible single-letter DNA changes. Here’s how it could help researchers better understand our biology 🧵
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AlphaFold: predicting the protein structure from amino acid sequence for >200 million proteins (awarded @NobelPrize) Today Alpha Genome Atlas: predicting the molecular impact of all 9 billion variants of the human genome nature.com/articles/d41586-0…
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