Y Combinator
@ycombinator • 1,646,117 subscribers
We help founders make something people want. Subscribe to our newsletter: https://t.co/sjqjxxBeLc
Shorts
Videos
YC W19's Heart Aerospace just flew the largest electric airplane ever flown. Seven years ago, co-founder & CEO Anders Forslund came to YC with a 3D-printed model you could hold in your hand. Today, the aircraft has a 100-foot wingspan, weighs 25,000 pounds, and costs just $5 in electricity to get off the ground. YC’s Gustaf Alströmer visited their pilot plant in LA to learn how they built it -- and what cheap electric flight could unlock for the future of regional air travel.
Y Combinator68,766 Aufrufe • vor 1 Tag
BioStack (getbiostack) builds simulation environments where healthcare AI models practice on real clinical data. Messy records, lab tests, notes, outcomes unfolding over months— BioStack turns that into a post-training loop: data, evals, rewards, benchmarks. They've grown from six figures to seven figures in revenue in just the last few weeks. Congrats on the launch, Sanat Mishra & Parth Patwa!
Y Combinator2,255,140 Aufrufe • vor 3 Monaten
Since the start of the year, OpenCode (YC W21) — an open source alternative to Claude Code and Codex that works with any model — exploded to 4.6 million weekly active users, 13 million monthly actives, and roughly $40M in annualized revenue. In this episode of The Lightcone, Harj Taggar, Jared Friedman, and Diana talk with Jay V (Jay), OpenCode’s CEO, about what’s driving this wild growth, the Anthropic clampdown that inadvertently fueled it, and the almost 20 year founder journey that led him here. 00:44 — OpenCode’s Explosive Growth 01:16 — 20x Growth, 13M Users, and 7 Trillion Tokens 03:39 — The Anthropic Controversy That Changed Everything 05:43 — Bringing AI Coding Agents to the World 06:39 — When Open Source Models Became Good Enough 08:56 — What Millions of Developers Are Actually Using 13:31 — Why OpenCode Is Huge Outside the US 15:27 — Why Fortune 500 Companies Choose OpenCode 16:36 — The Economics of AI Tokens 20:02 — How Enterprises Are Using Coding Agents 22:58 — AI’s New Unit Economics 24:56 — Why Model Choice Matters 29:55 — The Product Decisions Behind OpenCode 34:21 — A 16-Year Overnight Success 41:16 — Why Jay Never Gave Up
Y Combinator752,621 Aufrufe • vor 1 Monat
Kuli (Kuli) is the AI coworker that gives marketers their time back and makes them 10x more efficient. It watches all videos on socials to find the next trend and gets work done. Already live at Fortune 100 brands, it plans and runs their campaigns with creators. Congrats on the launch, Mike Hodara & Jonathan!
Y Combinator2,450,315 Aufrufe • vor 4 Monaten
A Cloud for Small Software Pete Koomen Agents make it easy to build personal tools for yourself or your team. But deploying, securing, and sharing that software is still far more complicated than creating it. A cloud built for small software could remove that complexity and make bespoke tools as easy to share with a colleague as a Google Doc.
Y Combinator688,676 Aufrufe • vor 1 Monat
AI agents will pay you to chat with them. When AI agents hit a wall, Humwork's (Humwork) MCP server connects them to a verified domain expert in 30 seconds. Their experts include senior engineers, marketers, designers, and more. Congrats on the launch, Yash Goenka and Rohan Datta!
Y Combinator1,787,382 Aufrufe • vor 4 Monaten
Chad IDE (cladlabs) is the brainrot code editor. AI coding takes 1–5 min between prompts—too long to ignore, too short to start something new. Chad integrates your brainrot (X, IG, Stake, Tinder, etc) into your agentic coding workflow and helps to manage your context-switching. Less doom-scrolling. More shipping.
Y Combinator3,874,851 Aufrufe • vor 9 Monaten
Today, more than 3% of the world's lawyers use Legora, and the company has grown from $1 million to $100 million in ARR since launching in October 2024. At Startup School 2026, Legora co-founder and CEO Max Junestrand shares how they built one of the fastest-growing enterprise software companies in the world, from cold emailing lawyers and moving into a customer's office to freezing sales for six months to rebuild the product. He explains why building a company is ultimately about people, how to create a culture that wants to win, and why founders have to learn to love the hustle. 00:07 — From 3 Engineers to $100M ARR 03:15 — How Legora Got Started 05:09 — Learning the Legal Industry From Scratch 07:22 — Getting Rejected by YC 09:36 — Moving Into a Customer's Office 11:11 — Going From Zero to $1M ARR During YC 13:26 — Why We Froze Sales for Six Months 15:18 — Rebuilding the Product From Scratch 17:26 — Building a Company Is About People 21:51 — Creating a Culture That Wants to Win 25:26 — You Have to Love the Hustle 27:55 — Do Founders Need Domain Expertise? 29:14 — Betting on Models Getting Better 36:29 — When Should You Start a Company? 45:04 — How to Become More Ambitious 48:18 — The Skills Founders Need Today
Y Combinator75,768 Aufrufe • vor 7 Tagen
Stage is a code review platform designed to help engineers understand AI-generated code. Your team is drowning in an endless backlog of PRs. Stage turns code review into a guided process and enables you to review changes faster than using GitHub. Congrats on the launch, Charles Pan and Dean Stratakos!
Y Combinator1,063,689 Aufrufe • vor 3 Monaten
Company Brain Tom Blomfield Every company has critical know-how scattered across people's heads, old Slack threads, support tickets, and databases, and AI agents can't operate like that. We think every company in the world is going to need a new primitive: a living map of how the company works that turns its own artifacts into an executable skills file for AI.
Y Combinator1,195,781 Aufrufe • vor 4 Monaten
Philip Johnston (Philip Johnston) is the co-founder and CEO of Starcloud, the company building data centers in space. In November 2025, Starcloud launched an Nvidia H100 GPU into orbit and trained the first large language model in space. They've since raised $200 million, hit a billion-dollar valuation just 17 months after YC demo day and filed with the FCC to deploy 88,000 more satellites. In this episode of Lightcone Podcast, Philip walks us through their wild origin story, the engineering challenges behind the Starcloud-1, why they booked a SpaceX launch before they even knew what they were building and how data centers in space make sense both economically and politically. 00:39 — Why Build Data Centers in Space? 01:40 — The Insight That Started Starcloud 04:43 — Launching Starcloud-1 09:45 — The Engineering Behind Data Centers in Orbit 13:49 — Why 100 VCs Said No 16:12 — Book the Launch Before You Build the Product 18:32 — The Roadmap to Commercial Space Compute 21:10 — Building NVIDIA GPUs for Space 23:41 — Raising $170M for a Hard Tech Startup 26:37 — Hiring the World's Best Space Engineers 31:25 — Why AI Compute Is Moving to Space 34:49 — Advice for Hard Tech Founders
Y Combinator229,182 Aufrufe • vor 28 Tagen
The next generation of startups will be built by smaller teams than ever before. At Startup School 2026, YC's Garry Tan explains why we're we're entering the era of personal AGI: AI agents that run on your own infrastructure, compound your knowledge over time, and dramatically increase your ability to build. He shares the tools and workflows he uses every day, why every founder should own their intelligence instead of renting it, and what it means to build under your own power. 00:07 — What Founders Can Learn From Spinoza 04:46 — Personal AGI Is Already Here 07:57 — Why AI Makes One Person More Powerful Than Ever 12:29 — Your Life Is a Library 15:15 — Inside My Personal AI System 17:06 — Markdown Is Code 18:20 — Latent Space vs. Deterministic Code 21:13 — Building a Company of One 24:16 — How to Build Your Own Personal AGI 27:58 — Why Most People Will Quit Too Soon 29:09 — Own Your Skills Before Someone Else Does 32:24 — Personal AGI Means Owning Your Intelligence 35:21 — Why I Open Sourced Everything 38:30 — A Personal AGI for One Small Boy 40:18 — It's All Made Up. You Get to Make It Up.
Y Combinator214,961 Aufrufe • vor 27 Tagen
Multiplayer AI Aaron Epstein The best work tools became more powerful when they became multiplayer. But AI is still mostly trapped in private chats, with agents working in sessions that teammates can’t join or influence. The next generation of AI tools will let teams work with agents together in real time: watching, redirecting, and handing off work across engineering, sales, support, legal, finance, and more. AI’s multiplayer moment is coming.
Y Combinator325,194 Aufrufe • vor 1 Monat
In 2001, Jeff Dean and Sanjay Ghemawat did the math and realized Google’s entire search index would fit in RAM — then shipped it in a few days, and search got fast. In 2013, another napkin calculation showed that three minutes of daily speech recognition per user would require doubling Google’s server fleet. That one became the TPU. At Startup School 2026, Google’s Chief Scientist talks with YC’s Diana through the thought experiments behind both, why inference hardware is the next specialization, and where two or three people in a room can still win. 00:07 — Are AI Models Already Junior Engineers? 01:44 — AI Systems That Improve Themselves 02:40 — The Google Search Breakthrough That Changed Everything 04:38 — AI Agents Will Run for Weeks 05:58 — The Napkin Math That Led to TPUs 09:20 — How to Find Breakthrough Ideas 10:25 — The AI Engineer's New Mental Model 12:33 — Why AI Is Really an Energy Problem 16:11 — Context Engineering Is the Next Frontier 19:46 — The Skill That Made AI Better at Optimization 22:13 — Why Long-Running Agents Fail 25:21 — Where Startups Can Still Beat Google 31:19 — How to Become an AI-Native Founder 36:36 — Question Your Biggest Assumptions 42:08 — AI That Builds Better AI 50:02 — Build Something That Truly Matters
Y Combinator255,989 Aufrufe • vor 1 Monat
