Spenser Skates has spent more than a decade building Amplitude from a YC startup into a public company, and in that time, he's had to reinvent himself just as much as the product.Joining the Lightcone pod, he talks through the shift from founder to large-company CEO, the skepticism his team initially had toward AI, and the moment they realized the next wave of analytics would require a full reset.He walks through the hard reorganizations, the bottom-up experiments, and the mindset changes that let Amplitude move fast again.

Logistics is a multi-trillion-dollar industry that quietly powers the entire global economy — and it's shockingly manual.Ryan Petersen, founder & CEO of Flexport, joins the Lightcone to break down how AI is finally touching the physical world: making shipping cheaper, speeding up global trade, and automating work that used to live inside emails, spreadsheets, and phone calls.

MIT's new State of AI in Business report went viral for claiming that 95% of enterprise AI projects fail. But the real story isn't that AI doesn't work — it's just big companies can't build it.In this episode of the Lightcone, Garry, Harj, Diana, and Jared break down what the study really says, why in-house enterprise AI efforts keep stalling, and how startups are filling the gap with products that learn, integrate, and actually deliver value.

Nine out of ten people might tell you you're crazy. The tenth might see what you see.Garry, Harj, Jared, and Diana talk about contrarian bets — the ideas that look impossible until they work. From Uber and Coinbase to DoorDash and Flock Safety, they share how founders find opportunity where others see dead ends.

In the early days, the only moat that startups have is speed. Once you make something people want, the question becomes what deeper moats can you build on to defend against the competition?Garry, Harj, Diana, and Jared dive into Hamilton Helmer’s Seven Powers framework to find out how these moats show up in practice today in AI startups.

Bob McGrew helped build some of the most influential technologies of the past two decades. Bob was an early engineer at PayPal, an early executive at Palantir, and was recently Chief Research Officer at OpenAI - where he led the development of ChatGPT, GPT-4 ,and the o1 reasoning model.During his time at Palantir, he was a pioneer of the Forward Deployed Engineer (FDE) model, a strategy that is at the heart of the AI boom today. On this episode of The Lightcone, he explains how FDEs became central to today's startups, why "doing things that don't scale at scale" works, and where he sees the biggest opportunities for founders working in AI.

Tom Brown co-founded Anthropic after helping build GPT-3 at OpenAI. A self-taught engineer, he went from getting a B-minus in linear algebra to becoming one of the key people behind AI's scaling breakthroughs. And his work is paying off.Today, Anthropic's Claude is the go-to choice for developers, and his team is overseeing what he calls "humanity's largest infrastructure buildout ever." On this episode of The Lightcone, he discusses his unconventional path from YC founder to AI researcher, the discovery of scaling laws that changed everything, and his advice for young engineers entering AI today.

AI has upended the once "safe" CS career path.New grads are facing unemployment rates twice those of art history majors, and a CS degree is no longer a surefire ticket to wealth. At the same time, small, focused teams are scaling from zero to eight-figure revenue in months.In a special Lightcone Live at AI Startup School, Garry, Diana, Harj, and Jared discuss why it's now more important than ever to focus on building real skills, domain expertise, and agency rather than just chasing credentials.

Alexandr Wang started Scale AI to help machine learning teams label data faster.It started as a simple API for human labor, but behind the scenes, he was tackling a much bigger problem: how to turn messy, real-world data into something AI could learn from. Today, that early idea powers a multi-hundred-million-dollar engine behind America's AI infrastructure—fueling everything from Fortune 500 workflows to real-time military planning. Just last week, Meta agreed to invest over $14 billion in Scale AI, valuing the company at $29 billion.Alexandr joined us on the Lightcone to share how Scale AI evolved from a scrappy YC startup into the backbone of some of the world's most advanced AI systems, how he thinks about competition with Chinese AI labs, and what it takes to build infrastructure that shapes the frontier.

At first, prompting seemed to be a temporary workaround for getting the most out of large language models. But over time, it's become critical to the way we interact with AI.On the Lightcone, Garry, Harj, Diana, and Jared break down what they've learned from working with hundreds of founders building with LLMs: why prompting still matters, where it breaks down, and how teams are making it more reliable in production.They share real examples of prompts that failed, how companies are testing for quality, and what the best teams are doing to make LLM outputs useful and predictable.The prompt from Parahelp (S24) discussed in the episode: https://parahelp.com/blog/prompt-design

There's never been a better time to start an AI company. Not just because there are new ideas, but because the tech finally makes old ones actually work.On the Lightcone, Garry, Harj, Diana, and Jared talk through the kinds of startups that are suddenly viable thanks to LLMs—from full-stack law firms to personalized tutors to recruiting platforms that can finally scale. They share the patterns they're seeing, the ideas they're excited about, and what it means to live at the edge of the future, where breakthroughs often look like second chances.If you've been waiting for the right moment to build, this is it.

Varun Mohan didn't set out to build one of the fastest-growing AI developer tools. He just knew his company had to change, or die.After initially betting on GPU virtualization, he saw the writing on the wall: if there was a future for his company, it would be at the AI application layer, not infra. Over a single weekend, he and his team pivoted to building Windsurf— a tool to help everyone, both technical and non-technical, write code faster and smarter.In this conversation, Varun shares the inside story of how they pivoted at the edge of failure, trained new models from scratch, outpaced giants like GitHub Copilot, and what the future of building with AI looks like.Apply to Y Combinator: https://ycombinator.com/applyWork at a startup: https:/workatastartup.com

Technical skills build startups—but oftentimes, people skills can save them. So how do you navigate the disagreements and conflict that inevitably arise with a co-founder? In this episode of the Lightcone, our hosts share what they've learned for managing these critical, yet often overlooked challenges, offering advice on how to handle the messy realities that go beyond building.

Andrej Karpathy recently coined the term “vibe coding” to describe how LLMs are getting so good that devs can simply “give in to the vibes, embrace exponentials, and forget that the code even exists.” In this episode of the Lightcone, the hosts discuss this new method of programming and what it means for builders in the AI age.Apply to Y Combinator: https://ycombinator.com/apply

The Lightcone hosts sit down with Aaron Levie, the co-founder & CEO of Box, to hear reports from the front of how large enterprise and Fortune 500 companies are adapting to the AI age.

Apply to AI Startup School in SF: https://events.ycombinator.com/ai-susThere’s never been a better time to launch an AI startup, but many prospective founders find themselves stuck when it comes to thinking of a good idea. In this episode, the Lightcone hosts look at different ways breakthroughs can be discovered.Apply to Y Combinator: https://ycombinator.com/apply

In this special episode of Lightcone, we’re joined by YC partner and creator of Gmail, Paul Buchheit, to dig into some of the latest trends in the world of AI and startups. We recorded our conversation at a recent retreat where 300 of the top AI founders in the world gathered to share expertise and make predictions about how this technology will shape our future. In the discussion, we cover a wide range of topics, including the future of work, the power of agency and taste in an AI world, and why this is the absolute best time to be building a startup.

Happy New Year! In this mini-episode, the Lightcone hosts ring in 2025 with their predictions for startups, AI, crypto, and more.

2024 has been quite a year for AI and startups. As we head into the holidays and the new year, the Lightcone hosts reflect on this year’s biggest startup trends, moments, and breakthroughs.

As AI models continue to rapidly improve and compete with one another, a new business model is coming into view: vertical AI agents. In this episode of the Lightcone, the hosts consider what effect vertical AI agents will have on incumbent SaaS companies, what use cases make the most sense, and how there could be 300 billion-dollar companies in this category alone.

There's an ongoing debate about whether AI scaling laws will hold or hit a wall in the near future. However, what's clear now is today's models already have the power to increase productivity in ways that would have been unimaginable even a few years ago. In this episode of the Lightcone, we dig into the results of a recent o1 hackathon hosted by YC to find out what can be unlocked when founders leverage a SOTA reasoning model.

Earlier this month, OpenAI raised the largest venture round ever at $6.6 billion. The company’s CFO says AI is now at the point where orders of magnitude matter and the next generation of models will be capital intensive. In this episode of the Lightcone, the hosts consider what a world with ultra-intelligent models would look like, and what potential unlocks could be made possible.

With rapid advancements in LLMs, AI can now follow prompts to generate code and build functional custom software. So, how does the tech landscape change when coding becomes accessible to everyone? In this episode of Lightcone, we sat down with Amjad Masad, CEO of Replit—an AI-powered platform for software development and deployment—to explore how anyone can now tap into the power of coding.

As LLMs continue to improve, it's clear that vertical AI agents are key to the next generation of billion-dollar SaaS opportunities. In this episode of the Lightcone, we sat down with Jake Heller, the co-founder and CEO of Castext— which sold to Thomson Reuters for $650 million in 2023— to discuss what it takes to build a successful vertical AI company.

Suhail Doshi, a YC alumni who previously founded Mixpanel and Mighty, has created a state-of-the-art (SOTA) AI image diffusion model with Playground. The app allows you to talk to it like a graphic designer and helps you create imagery and text for a wide variety of use cases. In this episode of Lightcone, Suhail sits down with the hosts to talk about his experience building Playground with his team and what it takes to make a SOTA model. Try Playground: https://playground.com/design Read Playground V3 Paper: https://arxiv.org/pdf/2409.10695

Familiar with the lore of Y Combinator? Then you'll know Jessica Livingston — one of the original co-founders who started YC back in 2005. On a recent visit to our SF headquarters, she shared with the Lightcone hosts the stories and decisions of the early days that would form the foundations of YC as we know it today.

Is the latest excitement around AI just another round of dot-com or crypto-style hype? The Lightcone hosts discuss where AI might be if the hype cycle is real, and what may remain once the buzz wears off. Apply to YC's first-ever Fall batch at ycombinator.com/apply.

It’s the first guest episode of Lightcone! The hosts sit down with Paul Buchheit, one of Google’s earliest employees, the creator of Gmail and current YC Group Partner. (He also came up with Google’s famous tagline “Don’t be evil.”) This discussion covers a wide range of topics including the future of AGI, the early days of OpenAI and the crucial importance of open source models.

As AI continues to evolve and advance, a line of thinking has emerged that humans will no longer need to learn how to write code in the future. If so, could this mean that a staff of ten or less could create a unicorn? The hosts of Lightcone analyze this prediction and discuss whether it has merit.

There's been a lot of news lately about the updates to some of the largest foundational AI models. But what does this mean for startups? How will future product releases from the AI giants effect the companies built on top of them? The hosts of Lightcone discuss how founders can take advantage of these developments and avoid being steamrolled by the competition.

Last month, YC hosted Startup School East, a one-day event in Boston for university students. As part of the event, the Lightcone Podcast did their first live stage recording specifically tailored for the students. When you're young and there are seemingly endless directions you could pursue in life, the hosts of the Lightcone Podcast make the case for why right now is the perfect time to start a start up.

What's happening in startups right now and how can you get ahead of the curve? In this episode of the Lightcone podcast, we dive deep into the major trends we're seeing from the most recent batch of YC using data we've never shared publicly before. This is a glimpse into what might be the most exciting moment to be a startup founder ever. It's time to build.

YC has become a surprising force in the hard tech world, funding startups building physical products from satellites to rockets to electric planes. In this episode of Lightcone, we go behind the scenes to explore how YC advises founders on their ambitious startups. We also take a look at a number of YC's hard tech companies and how they got started with little time or money.

If you read articles about companies like OpenAI and Anthropic training foundation models, it would be natural to assume that if you don’t have a billion dollars or the resources of a large company, you can’t train your own foundational models. But the opposite is true. In this episode of the Lightcone Podcast, we discuss the strategies to build a foundational model from scratch in less than 3 months with examples of YC companies doing just that. We also get an exclusive look at Open AI's Sora! Read more about the YC AI companies from this episode on our blog: https://www.ycombinator.com/blog/building-ai-models

In this episode of the Lightcone Podcast, YC Group Partners chart the evolution of San Francisco as the center of the startup world and how AI has brought everyone back to the city. They also talk about why YC chose to open our new HQ in the Dogpatch neighborhood of San Francisco and share their advice for new founders moving to the city for the first time.

In this episode of the Lightcone Podcast, YC Group Partners discuss the launch of the Apple Vision Pro and the potential of this new platform for new startups. This is a deep dive into the technical innovations Apple has made for this product, how this compares to the launch of the iPhone, and advice for founders interested in building in this space.

In the first episode of the Lightcone Podcast, YC Group Partners dig into everything they have learned working with the top founders building AI startups today. They share the ideas that are working particularly well, mistakes to avoid, and take a look at the competitive landscape among the current AI giants.