Alexandr Wang: Building Scale AI, Transforming Work with Agents & Competing With China
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.
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State-Of-The-Art Prompting For AI Agents
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
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31:26
Startups Ideas You Can Now Build With AI
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.
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Windsurf CEO: Betting On AI Agents, Pivoting In 48 Hours, And The Future of Coding
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
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How To Navigate Co-Founder Disputes
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.
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