
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
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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.
parul retweeted
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.
👀
$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
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…
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.
parul retweeted
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!!!
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
parul retweeted
The big lesson: marketing + distribution are insanely important.
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
parul retweeted
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 🤯🥺
parul retweeted
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
parul retweeted
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…
i gave astra a robot, a paint brush, and a camera then asked it to paint the golden gate bridge in real life!
it figured out how to control the robot, and progressively got better throughout its attempts. the timelapse is sick
parul retweeted
The Mac Mini crisis has two completely separate buyer groups crashing into each other.
Group 1: wants local inference. The M-series chip is pretty efficient at this. They're basically buying Mac Minis as cheap GPU alternatives
Group 2: wants macOS sandboxes for computer use and post-training. Doesn't care about the gpu at all. Just needs the os
Both groups are competing for the same machine and hence the shortage.
Btw Apple has a server that could solve this, but they have kept it exclusively for internal use. Just sell us the rack server, put 200 CPUs inside it, and let us run as many sandboxes as we can. Charge us for it. Nobody loses money here.
The FDA was sluggish long before AI. Now the mismatch is lethal.
Life-saving drugs and devices are arriving faster than the paperwork. The regulatory wall between discovery and patients is about to look indefensible.
We are on the cusp of a wave of new therapies for some of the worst diseases. But the world won’t benefit unless the US fixes its drug regulatory system. My new essay for @nytimes, on how slow clinical trials are now the biggest obstacle to curing cancer.
nytimes.com/2026/09/04/opini…
- I interviewed dozens of researchers, especially oncologists at leading U.S. centers. A striking consensus emerged: science is no longer the main bottleneck to new cancer drugs. It is our ability to test discoveries in patients through clinical trials.
- The cost of starting a Phase 1 trial in America has roughly doubled over the past decade. As a result, companies increasingly take early trials abroad: Australia’s Phase 1 trial volume has nearly doubled in a decade, driven mainly by U.S. companies.
- Unfortunately, the underlying incentives are badly asymmetric: Institutions can be blamed for harms caused by moving too fast, but almost no one is blamed when patients deteriorate during avoidable delays. One doctor called the emerging system “ritualized safety over actual risk assessment.” Or as, @DavidHongMD put it: "We often forget that the biggest risk is the cancer itself."
- This problem is becoming more urgent because medicine itself is changing. Sequencing, biological engineering and A.I. make increasingly personalized therapies possible. But our regulatory system was mostly built for standardized drugs tested in large populations.
- @sytse, the co-founder of GitLab, shows what personalized medicine can achieve: after relapsed osteosarcoma and being told there were no options left, he pursued a highly individualized approach and has now been cancer-free for a year. But doing so required extraordinary resources and regulatory expertise.
- Pierce Ogden’s father was less lucky. After molecular analysis identified a drug that might target his glioblastoma, the manufacturer agreed to provide it. But administrative barriers delayed access until it was too late. “My dad was ready to try anything,” Pierce told me. “But the system is paternalistic.”
- The A.I. revolution is making this bottleneck more important, not less. A.I. relies on relevant data. Information from early-stage trials could compound with A.I. tools to achieve truly revolutionary medicines. Without the data, this is far less likely to happen.
- Another important shift is that innovation increasingly comes from academic labs and small biotech companies rather than Big Pharma. These small companies find it far harder to unable to absorb delays and regulatory barriers.
- Apart from cancer, China is the biggest winner from America's outdated medical regulations. China has a much faster trial system, with testing often starting a full year earlier. This allows Chinese pharmaceutical companies to experiment and improve medicines while American companies play with mice. Today, half of all drugs licensed by major pharmaceutical companies originate there, up from less than 5 percent only a decade ago.
- But we don't need to copy China. The best model is Australia: lots of on-site scientific and ethics reviews, and requirements that are proportionate to small, early-stage trials. Phase 1 studies there begin roughly 6–12 months faster, without any notable increases in adverse safety events.
- Operation TrialBlazer, a 2026 HHS initiative is a good start in this direction, but we need legislative action by Congress to truly make Phase I trials faster and more efficient!
I want to thank everyone who helped me with this article: everyone I interviewed and the amazing editors at the Times. This is the result of a months long journey of extensive interviews and research.
Special thanks go to those who came on the record. One of the features of the system is an atmosphere of fear, where practitioners are afraid to publicly come out and explain these issues. So anyone who does is a hero in my book!
parul retweeted
The internet is almost entirely unprepared for a future where everyone’s personal agents are running around executing tasks for them.
There are going to be endless new challenges and opportunities at the infrastructure layer, for user experiences, new business models, and more.
Totally fair action from Resy tbh just asked Instinct for its activity log and holy hell lol
"Total: roughly 200 API requests per hour, around the clock
1. 4 Charles availability sweep every 10 minutes, 24/7 since Friday morning - each run hit their API ~17-19 times (one per date in a 21-day window). ~100-115 calls/hour
2. Every morning at 9am drop time, a 2.5-minute burst polling every 0.4 seconds - 200-375 requests per drop
3. Occasional session-token refreshes"
“We are facing a transition to a world with incredibly intelligent machines, and we need to ensure that transition works out well for humanity. We need to find ways to preserve human agency and enshrine an intrinsic value to being human, in a world where most tasks could be performed by AI. To prevent extreme concentration of power in a world where undertakings that would have taken thousands of experts now will be achievable by a few people operating a large computer. And to ensure that humans remain in control of the future and are not left behind by unchecked progress, brought about by an alien intellect exceeding our own.”
From the official @OpenAi blog.
I wrote about the state of AI, why I’m concerned about the next few years, and the choices we need to make to keep the future in humanity’s hands.
An Alien Mind: openai.com/index/an-alien-mi…




























