Poetiq is a new startup founded by former DeepMind researchers that recently achieved a major jump on the ARC-AGI and Humanity's Last Exam benchmark by layering a recursive self-improvement system on top of existing models. In this episode of Lightcone, Poetiq's Founder & CEO Ian Fischer joined us to discuss how small teams can build “reasoning harnesses” that outperform base models, what that means for startups and why automating prompt engineering may be one of the most powerful levers in AI today.Chapters:00:00 – Intro00:40 – What Is Poetiq?01:07 – Recursive Self-Improvement Explained02:07 – The Fine-Tuning Trap02:59 – “Stilts” for LLMs03:14 – Recursive Self-Improvement vs. Fine-Tuning05:05 – Taking the Top Spot on ARC-AGI06:37 – Beating Claude on Humanity’s Last Exam08:40 – How the Meta-System Works10:26 – Beyond RL: A New S-Curve11:32 – Automating Prompt Engineering13:37 – From 5% to 95% Performance14:50 – Early Access & Putting Your Agent on Stilts16:17 – From YC Founder to DeepMind Researcher18:29 – Advice for Engineers in the AI EraApply to Y Combinator: https://www.ycombinator.com/applyWork at a startup: https://www.ycombinator.com/jobs

With the takeoff of OpenClaw and MoltBook, a new agent-driven economy is taking shape.

In this episode of the Lightcone, we took a look at the explosive growth of AI dev tools and whether the time has come for builders to make something agents want.

A very special guest on this episode of the Lightcone! Boris Cherny, the creator of Claude Code, sits down to share the incredible journey of developing one of the most transformative coding tools of the AI era.

In the AI era, startups aren't winning by hiring faster — they're winning by automating as many internal functions as possible. In this episode of Main Function, Garry breaks down how tiny teams are beating companies 20x their size by building automations into every workflow, from engineering to ops to customer support.

You’ve probably already heard all about OpenClaw (formerly Clawdbot/Moltbot). The viral sensation is an open-source AI assistant that runs on your own device, connects with messaging apps you already use, and goes beyond chat to actually execute tasks like managing your email, calendars, files, workflows, and more. Now meet the man behind it. YC’s Raphael Schaad sat down with Peter Steinberger, the creator of OpenClaw, to discuss the “aha” moment behind the viral personal AI agent, why local-first agents could replace many of today’s apps, and how personal agents will reshape the future of software.

Chapters:

00:00 – OpenClaw takes over the internet

00:44 – Life after going viral

01:28 – Why OpenClaw took off, what sets it apart

02:56 – Bots talking to bots (and hiring humans)

04:11 – From “God AI” to swarm intelligence

05:07 – Peter’s original “aha” moment

06:38 – Rebuilding the agent as a conversation

07:38 – The moment it exceeded expectations

10:21 – Are apps going to disappear?

12:31 – Memory, data silos, and ownership

14:39 – The privacy reality of personal agents

15:05 – Letting the bot loose in public Discord

16:55 – Giving an agent a personality

18:19 – Contrarian building philosophy

20:09 – CLIs vs MCPs

21:28 – Building for humans first

21:46 – The road ahead

Apply to Y Combinator: https://www.ycombinator.com/apply

Work at a startup: https://www.ycombinator.com/jobs

Wondering why your maker-turned-manager suddenly seems distracted in meetings? Maybe they're addicted to coding agents! In this episode of Lightcone, Calvin French-Owen — a co-founder of Segment and former engineer on OpenAI's Codex team — joins us to talk about why coding agents suddenly feel so powerful, the differences between Codex, Claude Code, and Cursor, and what the future of work will look like.

When you're starting out, it isn’t enough to just build a minimum viable product. You also need a minimum evolvable product - one that can adapt to the needs of those critical early customers. In this episode of Main Function, YC General Partner Ankit Gupta offers an update to the classic MVP playbook. He’ll outline strategies for getting your first customers, the power of adaptability and how feedback from early users will ultimately shape the future of your product and your company.

Apply to Y Combinator: https://www.ycombinator.com/apply

Work at a startup: https://www.ycombinator.com/jobs

Chapters:

00:00 – The Minimum Evolvable Product

00:46 – Finding the First Believers

01:29 – Counterintuitive Rules To Get Early Users

02:10 – Learn Fast, Don’t Fear Churn

02:52 – How Early Users Shape the Market You Enter

04:22 – Tesla Case Study

05:14 – How To Build To Evolve

Stoke Space is racing to build the world's first fully reusable rockets that can launch, survive reentry, and fly again and again. In this episode of Hard Tech, YC’s Aaron Epstein sits down with Stoke Space co-founders Andy Lapsa and Tom Feldman to find out why they chose to take on one of the hardest problems in rocket science, how an obsession with efficiency gives them an edge, and what full reusability could unlock for the future of spaceflight.

Apply to Y Combinator: https://www.ycombinator.com/apply

Work at a startup: https://www.ycombinator.com/jobs

2025 was the year AI stopped feeling chaotic and started feeling buildable. In this Lightcone episode, the YC partners break down the surprises of the year, from shifting model dominance to why the real opportunity is moving back to the application layer, and why the next wave of AI startups may be just getting started.

ARC-AGI is redefining how to measure progress on the path to AGI - focusing on reasoning, generalization, and adaptability instead of memorization or scale.

During this month's NeurIPS 2025 conference, YC's Diana Hu sat down with ARC Prize Foundation President Greg Kamradt to find out why most AI benchmarks fail, how ARC-AGI reveals the limits of today’s models, and why measuring intelligence may be harder than building it.

Head of Design Ryo Lu helped transform Cursor from a feature-layer on top of VS Code into one of the world's leading AI code editors.He joins YC's Aaron Epstein on Design Review to talk about the path that brought him to Cursor, how rapid prototyping reshaped the core product and how he's breaking down the barriers that once separated designers and coders.