Y Combinator

Why Inference Matters 12x More Than Training | YC Paper Club

This week’s Paper Club is all about inference. For every FLOP spent training a model, roughly six go to serving it each year — and getting that part right has produced over $220 billion in market cap

This Is How You Should Actually Make Launch Videos

There’s a misconception that a successful launch video needs to cost tens of thousands of dollars and feel like a high production commercial. But Farza Majeed has a radically different approach. Farza

How To Stand Out In A World Of AI Designs

Magic Patterns (W23) is one of the fastest-growing design tools in AI, helping product teams turn ideas into interactive, code-backed prototypes in minutes. Alex Danilowicz and his co-founder, both fr

AI Safety Fact vs. Fiction | YC Paper Club

This week’s Paper Club is all about AI safety - not the headlines, the science. AI safety has been a research field for decades, with its own conferences, methods, and a track record in systems like a

Demis Hassabis: Put your life force into a problem that matters

Alexandr Wang on what matters in an age of abundant intelligence

What surprised PG about AI

How Jeetu Patel Runs Cisco Like the World’s Largest Startup

Cisco is building AI infrastructure, from networking GPU clusters to securing agents, with its hyperscaler AI business reaching $9.3 billion in orders in two years. Cisco President and Chief Product O

A camera that can see through walls

Applied Electrodynamics is building cameras that can see through walls and other opaque materials. Using radio waves, their system can see through drywall, marble, and other surfaces to locate studs,

What If We Stopped Using GPUs? | YC Paper Club

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, the

Robotic factories that build robots

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 bec

Robot-Use Agents: Why General-Purpose Models May Win in Robotics

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

Rocket cargo delivery anywhere on Earth in minutes

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

Autonomous construction on Earth and beyond

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 critic

Drone swarm defense

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

The State of Startups in 2026

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

Why You're Getting Zero Replies To Your Cold Emails

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 Christina Gilbert

Mass Magnetics: USA-made magnetics for robotics and defense

Magnets are becoming critical to the future of robotics, defense, and other major US industries. But 90% of rare earth magnet material is conventionally thrown away. The team at Mass Magnetics are rec

Happy Alumni Demo Day!

Introducing Early Access: An Invite only program for the Enterprise

Introducing the YC Early Access Network. 4x a year, senior technology leaders get early looks at YC's enterprise AI companies and help shape their roadmaps. Invite-only, by application. Fall '26 kicks