Y Combinator(@ycombinator)

Congrats to @vitalize_care (YC W23) on their $31M Series A! They're building the AI operating syste...

Y Combinator (@ycombinator) — Wed, 07 Oct 2026 17:17:45 GMT

Congrats to @vitalize_care (YC W23) on their $31M Series A!

They're building the AI operating system for hospital staffing, scheduling, and capacity.

Nurse managers often lose two to four hours every day building schedules by hand, time that could be going to patients. Vitalize now manages millions of shifts a week across 15+ health systems, saving clinical leaders more than 2,000 hours a day. St. Luke's Health cut its overtime and agency labor spend by 54% within 12 weeks.

fiercehealthcare.com/health-tech/vi…

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Congrats to @multiplylabs (YC S16) on their $75M Series B! They build robots that manufacture the ...

Y Combinator (@ycombinator) — Tue, 06 Oct 2026 18:22:31 GMT

Congrats to @multiplylabs (YC S16) on their $75M Series B! 

They build robots that manufacture the world's most complex drugs, including gene therapies and mRNA treatments.

AI is speeding up drug discovery, but someone still has to physically make the medicines, and today that work mostly happens by hand. Manual production is slow, vulnerable to contamination, and can cost more than $1 million per dose for some gene therapies. Multiply's robots run that production inside facilities at AstraZeneca and Legend Biotech.

businessinsider.com/see-the-pitch-…

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Congrats to @sensible_bio (YC S21) on their $47M Series A! They engineer living cells to manufactur...

Y Combinator (@ycombinator) — Mon, 05 Oct 2026 18:00:01 GMT

Congrats to @sensible_bio (YC S21) on their $47M Series A!

They engineer living cells to manufacture mRNA, turning the cell itself into the factory.

Today's mRNA is made in cell-free processes that work fine for vaccines, where doses are small. The next generation of mRNA medicines, like in vivo CAR-T and gene editing, needs far higher doses and far purer mRNA than those methods can deliver.

Sensible is closing that gap with a platform that can already produce around 1,000 mRNA sequences per week. endpoints.news/sensible-bio-s…

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Congrats to @kiwicopple, @AntWilson, and @supabase on their $150 million round at a $10.65 billion v...

Y Combinator (@ycombinator) — Fri, 02 Oct 2026 19:40:00 GMT

Congrats to @kiwicopple, @AntWilson, and @supabase on their $150 million round at a $10.65 billion valuation!

More than 13 million developers use Supabase as the backend for their apps. They're adding more than 1 million users and over 4 million databases every month, and 70% of new databases are now created by agents or AI-driven tools.

nytimes.com/2026/10/02/bus…

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Applied Electrodynamics is building cameras that can see through walls and other opaque materials. ...

Y Combinator (@ycombinator) — Fri, 02 Oct 2026 19:07:06 GMT

Applied Electrodynamics is building cameras that can see through walls and other opaque materials.

Using radio waves, they can locate studs, pipes, cables, and junction boxes behind surfaces like drywall or marble and turn it into a dimensionally accurate 3D model.

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Gumloop (YC W24) is building a platform that lets employees across a company build and share AI agen...

Y Combinator (@ycombinator) — Fri, 02 Oct 2026 16:15:00 GMT

Gumloop (YC W24) is building a platform that lets employees across a company build and share AI agents, while giving IT control over the data, permissions, and infrastructure behind them. 

Today it’s used by companies including Shopify, Gusto, and Instacart to automate work across sales, customer success, operations, and more.

In this fireside, @gumloop co-founders @MaxBrodeurUrbas and @rbehal1729 joined @gustaf to share how they built Gumloop before models were ready for agents, then found product-market fit as the technology caught up. They talk about landing early enterprise customers, making companies AI-native, and why the people closest to the work should be the ones automating it.

00 — The AI Agent Builder for Every Team
38 — From Workflow Automation to Enterprise AI
20 — What It Takes to Win Enterprise Customers
02 — How the Founders Met and Got Into YC
00 — How Gumloop Uses Its Own Agents
02 — Landing Shopify and Rethinking Pricing
23 — Fundraising and the Limits of Staying Lean
35 — Letting Employees Automate Their Own Work
43 — Building Agents Companies Can Control
23 — Getting IT to Say Yes

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https://t.co/U12sl5x64x

Y Combinator (@ycombinator) — Fri, 02 Oct 2026 16:15:00 GMT

youtu.be/kDLji2s7LV4

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Tune in: https://t.co/AoGdMFZ98a

Y Combinator (@ycombinator) — Fri, 02 Oct 2026 14:18:23 GMT

Tune in: youtu.be/xc2FTBGRSJo

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Join us for the next Paper Club, where we'll talk AI Safety: https://t.co/SF0SkOM9bl

Y Combinator (@ycombinator) — Fri, 02 Oct 2026 14:18:23 GMT

Join us for the next Paper Club, where we'll talk AI Safety: events.ycombinator.com/yc-paperclub-o…

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This week’s Paper Club is all about alternative compute. Modern AI has been shaped by a tight coupl...

Y Combinator (@ycombinator) — Fri, 02 Oct 2026 14:18:22 GMT

This week’s Paper Club is all about alternative compute.

Modern AI has been shaped by a tight coupling between transformers, backpropagation, and GPUs. But as compute efficiency starts to plateau, there may be very different ways to build the machines that come next.

We explore what AI compute could look like beyond conventional digital hardware through optical systems that use light to perform computation, neuromorphic architectures inspired by the brain, and experiments teaching living brain cells to play Doom.

07 — @FrancoisChauba1: Why Alternative Compute?
38 — Beyond Backpropagation
08 — Zero-Order Optimization and SOMA
06 — Ilker Oguz: Computing With Light
27 — Why Optical Computing Isn’t Everywhere Yet
23 — Building a Diffusion Model With Light
03 — Optical Computing Q&A
00 — @AlokVasudev: What Is Neuromorphic Computing?
23 — What the Brain Can Teach Us About Chips
35 — Where Neuromorphic Computing Stands Today
24 — Neuromorphic Computing Q&A
04:24 — @vytalow: Teaching Brain Cells to Play Doom
07:48 — Training Biological Neurons With Reinforcement Learning
12:28 — How Brain Cells Learn From Feedback
15:40 — Biological Computing Q&A

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Startup School is coming to Taipei on November 12! 🇹🇼 Hear from founders like @andyfang of DoorDa...

Y Combinator (@ycombinator) — Fri, 02 Oct 2026 01:05:24 GMT

Startup School is coming to Taipei on November 12! 🇹🇼

Hear from founders like @andyfang of DoorDash, @jeffchanginvest of Vest, @moseslo of Xendit, @mchiang0610 of Ollama, and more.

And join builders and hackers from across Asia for a day of talks and sessions with YC partners.

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RSVP here: https://t.co/czwYVNAneH

Y Combinator (@ycombinator) — Fri, 02 Oct 2026 01:05:24 GMT

RSVP here: events.ycombinator.com/startup-school…

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We’re excited to welcome @vivianmshen and @raphaelschaad as YC’s newest General Partners! Vivian an...

Y Combinator (@ycombinator) — Thu, 01 Oct 2026 17:36:06 GMT

We’re excited to welcome @vivianmshen and @raphaelschaad as YC’s newest General Partners!

Vivian and Raphael first came to YC as founders.

Vivian co-founded Juni Learning (W18), which teaches kids coding and math, and later founded Acely, an AI tutor for college prep. Raphael founded Cron (W20), the calendar app that became Notion Calendar.

They built products used by millions of people, then returned to YC as Visiting Partners to help other founders. Now they're doing it full-time.

ycombinator.com/blog/welcome-v…

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https://t.co/9NBvecbiDC

Y Combinator (@ycombinator) — Thu, 01 Oct 2026 15:32:49 GMT

youtu.be/0-g2-PRrOdw

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Halluminate is building reinforcement learning environments and benchmarks to help AI models do know...

Y Combinator (@ycombinator) — Thu, 01 Oct 2026 15:32:48 GMT

Halluminate is building reinforcement learning environments and benchmarks to help AI models do knowledge work beyond coding, starting with finance. 

With a team of fewer than 10 people, the company works with four of the top five closed-source US AI labs and recently raised a $30M Series A.

In this fireside, co-founders @Jerr_Wu and @wgm752 sit down with YC's @xuster to share how testing browser agents led them to building the environments models now use to practice tasks like financial modeling. They explain why better verification, not just more training tasks, is critical to making models smarter, and how that work could eventually lead to simulated companies where teams of AI agents learn to work together.

00:00 — Halluminate’s Pivot From Evals to Training Environments
03:48 — Teaching AI to Do Financial Work
07:13 — Why Verification Matters More Than Volume
10:13 — From Finance to Simulated Companies
13:30 — AI Safety and Building the Team

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Live from DC with NASA Administrator Jared Isaacman (@NASAAdmin) https://t.co/7A8r3jfSf8

Y Combinator (@ycombinator) — Wed, 30 Sep 2026 17:34:23 GMT

Live from DC with NASA Administrator Jared Isaacman (@NASAAdmin)

x.com/i/broadcasts/1…

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We're hosting an evening in SF with @oakhcft and π for early-stage builders in physical AI: robotics...

Y Combinator (@ycombinator) — Wed, 30 Sep 2026 15:02:25 GMT

We're hosting an evening in SF with @oakhcft and π for early-stage builders in physical AI: robotics, autonomy, and intelligent hardware.

Join us for a fireside chat with @physical_int co-founder @QuanVng on what it takes to build in the physical world.

events.ycombinator.com/yc-oak-happyho…

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Y Combinator (@ycombinator) — Wed, 30 Sep 2026 13:35:22 GMT

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The Startup Industrial Base: Building for the Next 250 — Washington, D.C. https://t.co/7A8r3jfSf8

Y Combinator (@ycombinator) — Wed, 30 Sep 2026 12:56:34 GMT

The Startup Industrial Base: Building for the Next 250 — Washington, D.C. x.com/i/broadcasts/1…

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Tensr is building robotic factories that build robots. Their 12,000-square-foot factory is already ...

Y Combinator (@ycombinator) — Mon, 28 Sep 2026 20:51:24 GMT

Tensr is building robotic factories that build robots.

Their 12,000-square-foot factory is already making humanoids, end effectors, and even robots for the International Space Station.

Every order becomes training data for the factory to manufacture the next one better.

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“Tradeoffs that only pay off in 10 years will usually be underpriced.” Play the long game. When you...

Y Combinator (@ycombinator) — Sun, 27 Sep 2026 17:06:33 GMT

“Tradeoffs that only pay off in 10 years will usually be underpriced.”

Play the long game. When you think in decades rather than quarters, you’ll see that your potential customers have trajectories, not fixed sizes.

Paul Graham on making startups more powerful:
paulgraham.com/powerful.html

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One of the biggest surprises in AI over the last few years has been how well coding agents generaliz...

Y Combinator (@ycombinator) — Sat, 26 Sep 2026 14:35:20 GMT

One of the biggest surprises in AI over the last few years has been how well coding agents generalize beyond software. 

In a recent essay, MIT professor Philip Isola argued that we may be entering the era of robot-use agents: general-purpose models that can control different robots, write policies, and learn new physical tasks with little or no robot-specific training.

In this episode of Decoded, we're joined by the founders of @theWaddleLabs and @Robocurve, two of the startups whose work helped drive this realization. They're working at the frontier of using general-purpose models to control robots, and their recent demos helped inspire the growing conversation around robot-use agents. 

Together, we dig into the research behind that idea, from code-as-policies and vision-language-action models to the harnesses and evals needed to make these systems work in the real world.

00:00 — What Are Robot-Use Agents?
02:11 — From Vision-Language-Action Models to General LLMs
04:07 — The Bitter Lesson for Robotics
07:04 — How Coding Agents Learned to Control Robots
10:41 — How Robots Learn From Experience
14:22 — The Harness as a Form of Robot Intelligence
16:14 — Watching Astra Control a Robot
20:55 — Why General Models May Win in Robotics
26:05 — How Close Are General-Purpose Robots?

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https://t.co/m7H3GomCk5

Y Combinator (@ycombinator) — Sat, 26 Sep 2026 14:35:20 GMT

youtube.com/watch?v=Jv5B5C…

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Hop Aero is building rockets that can deliver cargo anywhere on Earth in minutes. They’re starting ...

Y Combinator (@ycombinator) — Fri, 25 Sep 2026 18:05:18 GMT

Hop Aero is building rockets that can deliver cargo anywhere on Earth in minutes.

They’re starting with military logistics and other time-sensitive payloads, including temperature-controlled materials with short shelf lives, where getting something there much faster can materially change the outcome.

They’ve already built and successfully hot-fired a new rocket engine, and signed $1.37B in commercial LOIs.

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https://t.co/zmwj8aZhG6

Y Combinator (@ycombinator) — Fri, 25 Sep 2026 15:23:14 GMT

youtu.be/2otGNwNOEUM

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Vapi (@Vapi_AI) is the platform for building and deploying voice AI agents. It now serves about a bi...

Y Combinator (@ycombinator) — Fri, 25 Sep 2026 15:23:13 GMT

Vapi (@Vapi_AI) is the platform for building and deploying voice AI agents. It now serves about a billion calls a year for companies including Amazon, Uber, and Intuit, helping businesses automate phone calls with AI.

Voice is becoming the default interface between businesses and their customers, but getting agents reliable enough for production is still much harder than it looks.

In this episode of Founder Firesides, co-founders @jordan_dearsley and @nikhilro_ sit down with @gustaf to share the long path to product-market fit, from pivoting more than a dozen times to building an AI therapist that eventually became the foundation for Vapi. They explain why voice was the first idea that felt inevitable, and how sticking with that conviction before the technology was ready eventually paid off.

05 — Powering a billion calls a year
12 — Why voice AI suddenly started working
57 — More than a dozen pivots
08 — From calendar app to AI note taker
23 — Starting over in San Francisco
14 — The AI therapist that became Vapi
56 — Finding PMF
47 — Why the model labs won’t replace Vapi
49 — The future of voice AI

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A lot of construction work is still done by hand simply because the machines to automate it don’t ex...

Y Combinator (@ycombinator) — Thu, 24 Sep 2026 20:07:36 GMT

A lot of construction work is still done by hand simply because the machines to automate it don’t exist. That’s become a bottleneck for building things like solar farms, data centers, and other critical infrastructure.

@cosmic_robotics is building those machines. Their robots have already installed 11,000 solar panels, and they just signed a major contract with the largest construction company in the country.

They’re building the construction robots we’ll need on Earth today, and eventually on the Moon and Mars.

@JamesAEmerick

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https://t.co/4WgjnSiWhM

Y Combinator (@ycombinator) — Wed, 23 Sep 2026 18:20:10 GMT

bloomberg.com/news/articles/…

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Congrats to Alex, Ben, and @hubble_network (YC W22) on their $200M Series C at a $1.6B valuation! ...

Y Combinator (@ycombinator) — Wed, 23 Sep 2026 18:19:57 GMT

Congrats to Alex, Ben, and @hubble_network (YC W22) on their $200M Series C at a $1.6B valuation! 

Hubble's satellite network lets any Bluetooth device connect directly to orbit with just a software update.

Cellular covers about 15% of Earth's landmass, and tracking anything beyond that has meant satellite hardware costing $25 or more per device. Hubble brings connectivity under 50 cents per device, which changes the math for billions of pallets, shipping containers, water pumps, and farm equipment that were never worth connecting before.

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Congrats to @SpamRoss, @mduvall_, and @numeral (YC W23) on their $100M Series C! Numeral automates ...

Y Combinator (@ycombinator) — Wed, 23 Sep 2026 16:25:00 GMT

Congrats to @SpamRoss, @mduvall_, and @numeral (YC W23) on their $100M Series C!

Numeral automates sales tax compliance end to end, from registrations and calculations to filings and payments.

They handle US sales tax plus VAT and GST across more than 90 countries, all in one system. More than 3,500 businesses run their compliance on Numeral, including Supabase, Eight Sleep, and Graza, with transaction volume up 327% in the past year.

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Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend...

Y Combinator (@ycombinator) — Wed, 23 Sep 2026 15:51:04 GMT

Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend their airspace.

Earendil Robotics is building autonomous interceptors, along with the software and training needed to stand up that capability from scratch. Their systems can take off, transit, and intercept targets on their own, reducing months of pilot training to a few clicks.

The goal is air defense that’s affordable enough to deploy in large numbers and simple enough to operate at scale.

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Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend...

Y Combinator (@ycombinator) — Wed, 23 Sep 2026 15:20:39 GMT

Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend their airspace.

Earendil Robotics is building autonomous interceptors, along with the software and training needed to stand up that capability from scratch. Their systems can take off, transit, and intercept targets on their own, reducing months of pilot training to a few clicks.

The goal is air defense that’s affordable enough to deploy in large numbers and simple enough to operate at scale.

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Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend...

Y Combinator (@ycombinator) — Tue, 22 Sep 2026 21:55:46 GMT

Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend their airspace.

Earendil Robotics is building autonomous interceptors, along with the software and training needed to stand up that capability from scratch. Their systems can take off, transit, and intercept targets on their own, reducing months of pilot training to a few clicks.

The goal is air defense that’s affordable enough to deploy in large numbers and simple enough to operate at scale.

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The YC Early Access Network is filling up fast. On Oct 22, tech leaders from high-growth startups t...

Y Combinator (@ycombinator) — Tue, 22 Sep 2026 20:14:06 GMT

The YC Early Access Network is filling up fast.

On Oct 22, tech leaders from high-growth startups to the Fortune 500 meet the best companies building enterprise AI.

Be in the room. Request one of the remaining spots in Early Access now.

events.ycombinator.com/yc-early-acces…

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Congrats to @CalebPeffer, @ericciarla, @nickscamara_, and @firecrawl on their $75M Series B! Firecr...

Y Combinator (@ycombinator) — Tue, 22 Sep 2026 17:50:00 GMT

Congrats to @CalebPeffer, @ericciarla, @nickscamara_, and @firecrawl on their $75M Series B!

Firecrawl turns the web into clean, structured data for AI agents, with more than 1.5 million people building on their API.

They're also launching Alexandria, a knowledge library where agents can search the live web, official data providers, and dedicated indexes of scientific papers, developer docs, and government records. Providers get paid when agents use their data, and Firecrawl plans to open that up to anyone with knowledge worth sharing.

firecrawl.dev/blog/introduci…

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https://t.co/yPfiNzTp3t

Y Combinator (@ycombinator) — Tue, 22 Sep 2026 15:00:03 GMT

youtu.be/htAl33M5F54

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Confido (@confidotech) is building the AI workforce for consumer brands, automating everything from ...

Y Combinator (@ycombinator) — Tue, 22 Sep 2026 15:00:02 GMT

Confido (@confidotech) is building the AI workforce for consumer brands, automating everything from accounting to sales and demand planning. They work with brands like Olipop and Dude Wipes, as well as divisions of Mars and Unilever, and recently raised a $55 million Series B led by Insight.

In this episode of Founder Firesides, Confido co-founders Justin Hunter and Kara Holinski join @sdianahu to share how they found a huge opportunity in an industry still running on spreadsheets and manual processes, and why selling the work rather than the software helped them win large enterprise customers.

04 — What Confido Does
16 — A Year of Pivoting
14 — Finding a Painful Problem in CPG
16 — Selling the Work, Not the Software
13 — The Future of Confido

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Y Combinator (@ycombinator) — Mon, 21 Sep 2026 21:15:48 GMT

x.com/i/broadcasts/1…

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Congrats to @angle_health (YC W20) on their $200M Series C at a $2.7B valuation! They're an AI-nat...

Y Combinator (@ycombinator) — Fri, 18 Sep 2026 17:23:58 GMT

Congrats to @angle_health (YC W20) on their $200M Series C at a $2.7B valuation! 

They're an AI-native health benefits platform built for small businesses.

Health insurance is one of the hardest, most regulated industries a startup can enter, and Angle is already profitable on a net-income basis with revenue more than doubling year over year. They oversee nearly $1 billion in annual premium equivalents for more than 5,000 small businesses, some with as few as two employees.

wsj.com/pro/private-eq…

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https://t.co/hx7k0GyCwi

Y Combinator (@ycombinator) — Fri, 18 Sep 2026 14:31:13 GMT

youtu.be/UKwpr_Trvns

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Kastle is building AI employees for banks. Its agents automate operations across mortgage servicing,...

Y Combinator (@ycombinator) — Fri, 18 Sep 2026 14:31:12 GMT

Kastle is building AI employees for banks. Its agents automate operations across mortgage servicing, consumer lending, and other back-office functions.

Today, Kastle works with 10 of the top 25 mortgage servicers and has processed more than $2 billion in transactions. The company recently raised a $24M Series A, just two years after going through YC.

In this episode of Founder Firesides, founders @therishic and Nitish join @sdianahu to share why they started over just one month before Demo Day, how they found their way into one of the hardest industries for deploying AI, and what it takes to make agents reliable enough to handle real financial transactions.

05 — What Kastle Does
00 — Why Banks Need AI Employees
50 — Going Back to Zero Before Demo Day
00 — Finding the Idea for Kastle
43 — Landing Their First Customer
18 — Moving Into a Customer’s Office
59 — The Future of AI Employees in Banking

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Tune in: https://t.co/qga4ugPX2S

Y Combinator (@ycombinator) — Thu, 17 Sep 2026 18:30:54 GMT

Tune in: youtu.be/yslXlV2BP_Y

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YC works with thousands of founders every year, which gives us an early look at how startups are cha...

Y Combinator (@ycombinator) — Thu, 17 Sep 2026 18:30:53 GMT

YC works with thousands of founders every year, which gives us an early look at how startups are changing. Right now, the shift is striking: startups are moving from bits to atoms, nearly one in five YC companies has a solo founder, and companies are reaching meaningful revenue faster than ever.

In this episode of the Lightcone, @garrytan, @snowmaker, @sdianahu, and @harjtaggar dig into what’s driving these changes and what they mean for founders. 

They discuss how AI is making it possible for smaller teams to take on more ambitious problems, why experienced founders are having a resurgence, and why knowing what to build is becoming more important than simply knowing how to build it.

06 — Startups Are Moving From Bits to Atoms
29 — Why AI Is Making Hard Tech Easier
21 — Defense, Manufacturing, and the Return of Hard Tech
48 — AI Compute Is Becoming a Physical Infrastructure Problem
34 — Robotics Is Approaching Its ChatGPT Moment
40 — Software Isn’t Dead. It’s Becoming the Harness
59 — Why AI Startups Are Growing Faster
52 — The Hidden Boom in Data and RL Environments
08 — Why Robotics Will Need Specialized Models
38 — The Rise of the Solo Founder
54 — Why Experienced Founders Are Back
59 — What Founders Should Do Right Now

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Raindrop (@raindrop_ai) is building the safety layer for AI agents. As agents get more capable and t...

Y Combinator (@ycombinator) — Thu, 17 Sep 2026 17:30:00 GMT

Raindrop (@raindrop_ai) is building the safety layer for AI agents. As agents get more capable and take on more complex work, Raindrop detects when they go wrong in production, from failed tool calls and hallucinations to problems companies didn’t even know to look for. Now they’re launching Raindrop Simulations, which brings that same approach earlier in the development process to catch failures before agents reach production.

Already used by companies including Vercel, Clay, Framer, and Speak, Raindrop just raised a Series A bringing its total funding to $50 million.

In this episode of Founder Firesides, founders @snarkyzk, @benhylak, and @alexisgauba sat down with @sdianahu to share how a tool they originally built to debug their own coding agent became the company, and why better AI agents actually create more ways for things to go wrong.

00:05 — What Raindrop Does
01:32 — Why Better AI Agents Create More Problems
03:25 — Finding the Failures Evals Miss
04:38 — How Raindrop Got Started
06:32 — Why They Kept Going
07:58 — Catching Agent Failures Before Production

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Y Combinator (@ycombinator) — Thu, 17 Sep 2026 17:30:00 GMT

youtu.be/5XO7ZEOGpJc

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Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend...

Y Combinator (@ycombinator) — Mon, 14 Sep 2026 18:07:54 GMT

Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend their airspace.

Earendil Robotics is building autonomous interceptors, along with the software and training needed to stand up that capability from scratch. Their systems can take off, transit, and intercept targets on their own, reducing months of pilot training to a few clicks.

The goal is air defense that’s affordable enough to deploy in large numbers and simple enough to operate at scale.

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Though most won’t even realize they’re using blockchains, we expect many teams to benefit with use c...

Y Combinator (@ycombinator) — Mon, 14 Sep 2026 16:49:17 GMT

Though most won’t even realize they’re using blockchains, we expect many teams to benefit with use cases like:

- Instantaneous and global payments for less than a cent
- Marketplaces settling with sellers in seconds
- Assets trading 24/7

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For too long, institutions were scared to invest and startups often skipped building for the US. Th...

Y Combinator (@ycombinator) — Mon, 14 Sep 2026 16:49:17 GMT

For too long, institutions were scared to invest and startups often skipped building for the US.

The US Clarity Act provides clarity for the next wave of builders. The Senate should pass it.

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The US CLARITY Act has an initial vote this week in the Senate. We’re bullish on the Clarity Act - ...

Y Combinator (@ycombinator) — Mon, 14 Sep 2026 16:49:16 GMT

The US CLARITY Act has an initial vote this week in the Senate.

We’re bullish on the Clarity Act - for the future of finance and for American fintech startups.

By specifying regulators and clarifying rules, Clarity makes it easier for American founders to build with blockchains.

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The best outbound starts before you automate anything. Founders need to learn who actually has the p...

Y Combinator (@ycombinator) — Sat, 12 Sep 2026 15:31:51 GMT

The best outbound starts before you automate anything. Founders need to learn who actually has the problem, what gets their attention, and what makes them reply. YC Visiting Partner @ChristinaG325 recommends doing at least your first 100 outreaches by hand so you can learn those things yourself.

Drawing from her experience generating and closing millions of dollars through founder-led sales at OneSchema, Christina shares eight ways founders can improve their outbound, from targeting the right people and writing emails worth reading to following up, debugging low reply rates, and using customer language to sharpen your message.

38 - Start manual before you automate
25 - Targeting beats perfect messaging
23 - How to find the right job titles
07 - Picking the right companies
47 - Intent signals
25 - Craft a message worth reading
00 - A cold email that works
19 - Subject lines
37 - Improve your LinkedIn profile
47 - What your reply rates are telling you
47 - Follow up, and reply fast
37 - Block out time for outbound
25 - Use the messaging from your customers
27 - Your slog compounds

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Y Combinator(@ycombinator)

Congrats to @vitalize_care (YC W23) on their $31M Series A! They're building the AI operating syste...

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Congrats to @sensible_bio (YC S21) on their $47M Series A! They engineer living cells to manufactur...

Congrats to @kiwicopple, @AntWilson, and @supabase on their $150 million round at a $10.65 billion v...

Applied Electrodynamics is building cameras that can see through walls and other opaque materials. ...

Gumloop (YC W24) is building a platform that lets employees across a company build and share AI agen...

https://t.co/U12sl5x64x

Tune in: https://t.co/AoGdMFZ98a

Join us for the next Paper Club, where we'll talk AI Safety: https://t.co/SF0SkOM9bl

This week’s Paper Club is all about alternative compute. Modern AI has been shaped by a tight coupl...

Startup School is coming to Taipei on November 12! 🇹🇼 Hear from founders like @andyfang of DoorDa...

RSVP here: https://t.co/czwYVNAneH

We’re excited to welcome @vivianmshen and @raphaelschaad as YC’s newest General Partners! Vivian an...

https://t.co/9NBvecbiDC

Halluminate is building reinforcement learning environments and benchmarks to help AI models do know...

Live from DC with NASA Administrator Jared Isaacman (@NASAAdmin) https://t.co/7A8r3jfSf8

We're hosting an evening in SF with @oakhcft and π for early-stage builders in physical AI: robotics...

Tweet

The Startup Industrial Base: Building for the Next 250 — Washington, D.C. https://t.co/7A8r3jfSf8

Tensr is building robotic factories that build robots. Their 12,000-square-foot factory is already ...

“Tradeoffs that only pay off in 10 years will usually be underpriced.” Play the long game. When you...

One of the biggest surprises in AI over the last few years has been how well coding agents generaliz...

https://t.co/m7H3GomCk5

Hop Aero is building rockets that can deliver cargo anywhere on Earth in minutes. They’re starting ...

https://t.co/zmwj8aZhG6

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A lot of construction work is still done by hand simply because the machines to automate it don’t ex...

https://t.co/4WgjnSiWhM

Congrats to Alex, Ben, and @hubble_network (YC W22) on their $200M Series C at a $1.6B valuation! ...

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Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend...

Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend...

Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend...

The YC Early Access Network is filling up fast. On Oct 22, tech leaders from high-growth startups t...

Congrats to @CalebPeffer, @ericciarla, @nickscamara_, and @firecrawl on their $75M Series B! Firecr...

https://t.co/yPfiNzTp3t

Confido (@confidotech) is building the AI workforce for consumer brands, automating everything from ...

https://t.co/4XSKWzYhps

Congrats to @angle_health (YC W20) on their $200M Series C at a $2.7B valuation! They're an AI-nat...

https://t.co/hx7k0GyCwi

Kastle is building AI employees for banks. Its agents automate operations across mortgage servicing,...

Tune in: https://t.co/qga4ugPX2S

YC works with thousands of founders every year, which gives us an early look at how startups are cha...

Raindrop (@raindrop_ai) is building the safety layer for AI agents. As agents get more capable and t...

https://t.co/j05yuKS3XN

Attack drones are reshaping modern warfare, but many countries still lack an effective way to defend...

Though most won’t even realize they’re using blockchains, we expect many teams to benefit with use c...

For too long, institutions were scared to invest and startups often skipped building for the US. Th...

The US CLARITY Act has an initial vote this week in the Senate. We’re bullish on the Clarity Act - ...

The best outbound starts before you automate anything. Founders need to learn who actually has the p...