--- title: Y Combinator's W25 Demo Day: hard tech takes center stage description: Y Combinator's W25 Demo Day featured 200 companies, with roughly a quarter classified as hard tech - a jump YC president Garry Tan says is 40x higher than... canonical: https://daily.dev/posts/y-combinator-s-w25-demo-day-hard-tech-takes-center-stage-6h7y6l1hg twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Y Combinator's W25 Demo Day: hard tech takes center stage | daily.dev og:description: Y Combinator's W25 Demo Day featured 200 companies, with roughly a quarter classified as hard tech - a jump YC president Garry Tan says is 40x higher than... og:url: https://daily.dev/posts/y-combinator-s-w25-demo-day-hard-tech-takes-center-stage-6h7y6l1hg og:image: https://api.daily.dev/og/posts/6h7y6L1hg.png og:image:alt: Y Combinator's W25 Demo Day: hard tech takes center stage og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Y Combinator's W25 Demo Day: hard tech takes center stage **[Collections](https://daily.dev/sources/collections)** · 2 min read · 0 upvotes · 0 comments ## Summary Y Combinator's W25 Demo Day featured 200 companies, with roughly a quarter classified as hard tech - a jump YC president Garry Tan says is 40x higher than three or four years ago. Investors singled out nine standout startups: Atomarine (floating nuclear-powered data centers, $4B in customer LOIs), Dipole Labs (optical networking skipping light-to-electricity conversion), Isengard (locally-produced jet-powered drones, $10M revenue), Lamb Labs (chips with AI weights hardcoded into hardware, called MPUs), an undisclosed robot training data company, Nori ($1,600 laundry-folding home robot), a heavy-lifting robotics company eyeing Mars construction, Parasma (training human brain cells to compute), and Waddle Labs (LLM-agent API generating robot control code). Despite the ambitious pitches, valuations across the batch were reported as more reasonable than in recent cohorts. ## Content Y Combinator's latest Demo Day featured 200 companies, and about a quarter of them were hard tech - a 40x increase from where that number sat three or four years ago, according to YC president Garry Tan. That shift showed up clearly in which startups investors were most excited about. VCs flagged nine companies as the buzziest of the batch, and the list reads less like a SaaS lineup and more like a science fiction reading list. **Atomarine** is building floating nuclear-powered data centers. They came in with $4 billion in customer letters of intent, which is either a sign of genuine demand or the most ambitious LOI stack anyone has ever assembled. **Dipole Labs** is working on optical networking for AI data centers that skips the light-to-electricity conversion step entirely - a meaningful efficiency gain if it works at scale. **Isengard** makes jet-powered drones that can be produced locally. They're already at $10 million in revenue, which puts them in a different category from most Demo Day companies. **Lamb Labs** is building chips with AI model weights hardcoded directly into the hardware, which they're calling MPUs. The pitch is that you get faster inference by removing the weight-loading step. There's also a robot training data company (name not disclosed), **Nori** - a $1,600 home robot focused on laundry folding - and a heavy-lifting robotics company with ambitions that apparently extend to Mars construction. **Parasma** is the strangest one on the list: they're training actual human brain cells to perform compute. That sentence is doing a lot of work. **Waddle Labs** rounds out the nine with an LLM-agent API that generates robot control code, which is a more grounded problem than some of the others but potentially just as important. Despite how ambitious most of these ideas sound, investors noted that valuations across the batch were more reasonable than in recent cohorts. Whether that reflects a correction in founder expectations or just the reality that floating nuclear reactors are harder to hype-price than another B2B SaaS tool is unclear - probably both. ## Similar posts on daily.dev - [The 11 standout startups from YC’s Demo Day, according to VCs](https://daily.dev/posts/the-11-standout-startups-from-yc-s-demo-day-according-to-vcs-p2zwzsmjd) · TechCrunch · 2 upvotes · 0 comments - [MIT startups inspire with impressive presentations at Demo Day 2026](https://daily.dev/posts/mit-startups-inspire-with-impressive-presentations-at-demo-day-2026-7dlfeddqs) · MIT News · 0 upvotes · 0 comments - [YC's Summer 2026 RFS bets on agriculture robots, drone defence, and lunar manufacturing as software loses its moat](https://daily.dev/posts/yc-s-summer-2026-rfs-bets-on-agriculture-robots-drone-defence-and-lunar-manufacturing-as-software--skizgfvxp) · The Next Web · 0 upvotes · 0 comments --- Tags: [#startup](https://daily.dev/tags/startup), [#venture-capital](https://daily.dev/tags/venture-capital), [#robotics](https://daily.dev/tags/robotics), [#y-combinator](https://daily.dev/tags/y-combinator) [View this post on daily.dev](https://daily.dev/posts/y-combinator-s-w25-demo-day-hard-tech-takes-center-stage-6h7y6l1hg) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Y Combinator's W25 Demo Day: hard tech takes center stage","url":"https://daily.dev/posts/y-combinator-s-w25-demo-day-hard-tech-takes-center-stage-6h7y6l1hg","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/y-combinator-s-w25-demo-day-hard-tech-takes-center-stage-6h7y6l1hg"},"datePublished":"2026-09-13T22:00:50.436Z","dateModified":"2026-09-13T22:01:28.017Z","description":"Y Combinator's W25 Demo Day featured 200 companies, with roughly a quarter classified as hard tech - a jump YC president Garry Tan says is 40x higher than...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/a57ee27ee56891948de94cbe56753b9b?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/a57ee27ee56891948de94cbe56753b9b?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Collections","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Collections","logo":"https://media.daily.dev/image/upload/s--fk_6ycEi--/f_auto,q_auto/v1780996001/logos/collections?_a=BAMAMiWQ0","url":"https://daily.dev/sources/collections"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/y-combinator-s-w25-demo-day-hard-tech-takes-center-stage-6h7y6l1hg","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"startup,venture-capital,robotics,y-combinator","timeRequired":"PT2M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Collections","item":"https://daily.dev/sources/collections"},{"@type":"ListItem","position":3,"name":"Y Combinator's W25 Demo Day: hard tech takes center stage"}]} ```