YC Visiting Partner, former CEO/Cofounder of Convex (acq by $TTAN), physical and vertical AI, services, & industrials investor. Dad.

San Francisco, CA
Joined February 2026
Charlie Warren retweeted
The top end of growth rates for companies riding an AI tailwind just keeps accelerating.
Replying to @sequoia
@sequoia is leading our Series C at a $1B valuation. We started Blacksmith in 2024 to make CI faster and less painful. In January we ran 5 million CI jobs a week. Today it's over 90 million and growing, and we’re still early.
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Biggest change since I started my company in 2017: the "design partnership." It's the Coach's Award of startup sales. Just ask for a paid contract and get used to 'no'
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All businesses will need new websites for agents. @MilesPines has (already) built the best product on the market. Incredible traction and incredibly happy customers across 10K+ sites.
Small businesses don't need a website builder. They need someone to do their marketing. They need Theo. @theo_site (YC F26) is the AI agent that builds - or rebuilds - your site, then works 24/7 to get you found on Google and in AI search. You run the business. Theo does the marketing. Free audit: theo.site
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Charlie Warren retweeted
Apply to YC and it will change your life We grew from $0 to $1M annualized revenue during the batch What you get from YC: → $500K investment → A cohort of ambitious founders who push you beyond your limits → Partners like @garrytan & @gustaf who have your back for life → $11.5M in perks and credits → Bookface + alumni founder community (also for life) → Demo Day in front of thousands of investors
Applications for the YC Winter 2027 batch are now open! Apply by November 2: ycombinator.com/apply
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Charlie Warren retweeted
*Over $11.5M in perks and deals btw
YC W27 applications are now open What YC gives you: → $500K investment → YC partners in your corner, for life → Faster launches, growth and customer acquisition → Demo Day in front of thousands of investors → Over $500K in credits and 100+ perks → Alumni include Airbnb, Stripe, DoorDash & Coinbase Truly a life-changing opportunity, one application away 🔸
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Charlie Warren retweeted
The percentage of solo founders at @ycombinator went from 3% to 20% in 2 years. In the age of AI, the right, motivated person is unstoppable.
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One of my favorite trends of the current era -- crazy ambitious founders going for the jugular of the SaaS incumbents 🩸
Today, we're launching Sazabi version 1.0. The reality of shipping software as a team in the age of AI is actually crazy. Agents merging their own PRs. Hundreds of deployments per day. A codebase that is constantly changing. Junior developers with 10x or 100x leverage. 😵‍💫 I spent the last year building a safety harness for teams that ship with AI. It's called @sazabi. The premise is simple: 1. You send us logs. 2. We detect anomalies, investigate them, and send you back rich, actionable alerts about real problems in your app. Sazabi helps you find issues before your users notice. No monitors or noisy alerts. Just pure signal. And today we're making it available for anyone to use.
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People forget that TTAN was one the first SaaS IPOs after the ZIRP correction. It was good, too!
My favorite quotes of the week: 1. “The SaaS era started with the IPO of Salesforce and ended with the IPO of ServiceTitan.” 2. “You should tweet that only 3 VCs matter.” 3. “Fee compression is going to kill most asset managers. Anyone with a brain should assemble a bunch of direct capabilities across asset classes and charge big pools 1% and 5% for a full direct portfolio.”
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In jest, there is truth
Upfront Heating & Air Conditioning
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Charlie Warren retweeted
It’s pretty clear to me that the internet is headed toward a new business model that we may not have figured out yet. Consumers will increasingly outsource tasks to agents, and agents will work around the clock to execute them on their behalf. These tasks require inference spend. The most obvious way to cover these costs is by passing them through to the user. Users pay a monthly subscription or simply pay for credits that get deducted as inference gets spent. But with the cost of inference dropping over time, this will ultimately be a race to the bottom. Pass-through pricing will get commoditized and won’t be able to sustain margins. So startups and incumbents will have no choice but to offer a different business model. Paying for task-based outcomes is an obvious iteration. You can imagine customers paying agents when they achieve certain goals, such as successfully booking an appointment or executing a refund the user wouldn’t have taken care of on their own. But most tasks aren't worth paying for one at a time. The most scaled business models on the internet let everyone participate, even when they can't pay directly. This is why advertising dominated as the primary business model of the past 30 years. Incumbents will subsidize usage dramatically over the next few years to onboard as many customers as possible. We’re already seeing this with Muse. But the question is, how will this work get paid for long-term? Can agents adopt a form of advertising that covers the cost? Or do we need a completely new model where the few big paid outcomes subsidize everyone else's usage? We may be headed toward a new world of haves and have nots. Or a world of abundance where everyone can get anything done at any time for free.
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I keep telling people -- Dunning-Kruger!
enterprise maturity arc with AI = Dunning–Kruger Stage 1: building with agent’s internally Stage 2: a lot f*kin’ harder than we thought Stage 3: take our $$$, here’s what we want; let’s go
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Charlie Warren retweeted
We’re launching OpenSEO, the open source alternative to Semrush. It started as a spite app, but now we're on track to build the best SEO tool for AI agents. We just shipped our AI Visibility Beta for GEO too. Hope you support!
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Charlie Warren retweeted
Your usage restrictions are my opportunity.
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Charlie Warren retweeted
On our quest to take down Semrush, we’re open sourcing AI Visibility. Getting mentioned by AI shouldn’t require another subscription. All of OpenSEO’s features for SEO/GEO are available for $10/month. I linked a demo video in the comments. Hope you try it out!
We just shipped some major AI Visibility features. Instead of paying $100+/month, on our $10/month plan you can: - See how AIs talk about your industry - Track responses over time - Compare against your competition - See which pages get cited What should we add next?
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Charlie Warren retweeted
If a founder built a startup in the database market in the mid-2010s, 2% market share meant the company could IPO. No surprise the database was the most important software category in that era. Inference is about to surpass it.
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Neil sold Servicemax to PTC, then became CEO of PTC, now $23bn all cash acquisition by my old customer, Schneider Electric. All in last few years. Congrats Neil and team.
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What if Apple (engineers) designed actuators? Robots should feel!
I’m excited to announce Silica. We make affordable actuators that sense forces directly, so that all robots can feel the world around them. We’re fortunate to receive early support from @fdotinc @ycombinator @UPPartnersVC. Check out our website below to learn more :)
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Companies need to new websites, build for agents not humans. Easy to say, hard to do without an insanely good product. But Theo is that good. Excited to work with @MilesPines
Hey everyone! I’m super-excited to share that my new venture, Theo (@theo_site), is now live and backed by @ycombinator. Check it out at theo.site We’ve built over 10,000 websites already and our early-adopters have seen an average 50% boost in traffic. Thank you!
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