Y Combinator

Unofficial, machine-generated summaries, as of 2026-11-09.

Startup School is back!
  • Multiple founders credit Startup School with their decision to apply to YC. Several describe it as the pivotal event that gave them "the courage to apply," with one saying their company's entire trajectory would look different without having attended first.
  • Seeing peers their own age build companies made founding feel achievable. Attendees point to hearing speakers like Fei-Fei Li and John Jumper the prior year as what "ignited the passion" to start a company, rather than any specific technical lesson taught.
  • The event is framed as an unmatched concentration of ambitious, skilled people. Attendees describe it as selecting specifically for founders who are smart, ambitious and technically capable, with the shared room of similarly driven peers cited as what convinced several of them to commit to starting now rather than later.
Emergent: How Six Months of Tinkering Led To A $100M ARR Company
synopsis

Mukund Jha, co-founder and CEO of Emergent, traces the company from the depressed aftermath of his previous startup's collapse to a nine-month-old business generating $100 million in annualized revenue, arguing throughout that unstructured tinkering and betting on where AI models are heading, not where they currently stand, explain the speed of the outcome.

Jha's prior company, Dunzo, had scaled to roughly a million delivery riders and 10 million monthly orders on $200 million-plus in funding before its 2023 collapse, which he says he initially caused by believing the company was "too big to fail." What followed was six months of what he calls pure, objective-free tinkering, up to twelve hours a day experimenting with new AI models, an escape from disappointment that also convinced him coding itself was about to be disrupted quickly.

Pitching that instinct to VCs went badly at first: roughly a dozen investors rejected the idea of automating software engineering, since AI copilots were the fashionable pitch of the moment and reviewers judged full automation unrealistic. Jha and his co-founder, his twin brother, responded by deliberately building toward an extrapolated, six-months-ahead version of what models would be capable of rather than their current state, for instance ignoring a JSON-output-parsing problem that roughly 20 to 30 other YC companies were separately trying to solve, betting the next model generation would simply fix it.

Lacking a settled product idea, the team spent three months chasing SWE-bench, the hardest available coding benchmark, partly as a way to stop the team from pivoting weekly; becoming the world's top-ranked system on it with four people became the technical base — parallelized test-time compute, cross-agent memory, custom container-snapshotting infrastructure — that the eventual product was built on. Jha says Emergent differentiates from earlier AI website builders by insisting on shipping real, working software with a genuine backend and database rather than front-end "demoware," a bet validated by outperforming competitors on head-to-head prompts.

He closes with advice for founders building from India: a global company is no harder to build than a local one given today's reach, so founders should think global from day one, trust their own intuition over conventional advice, and aim at ambitions ten to a hundred times bigger than their first instinct, since "it's not time to attack the floor, it's time to attack the ceiling."

  • Emergent reached $100M in annualized revenue nine months after launch. Mukund Jha, the company's co-founder and CEO, says the no-code app-builder lets anyone ship real, deployed software — including a working backend and database — just by chatting with an agent, unlike most competing tools he says only produce front-end "demoware."
  • Purposeless tinkering after his last company's collapse led directly to the idea. Jha says he spent up to twelve hours a day experimenting with new AI models with no business objective following the 2023 shutdown of his earlier startup Dunzo, and that period of pure curiosity generated the technical insight that coding itself was about to be disrupted.
  • Twelve VCs rejected the pitch to "automate software engineering." Jha says the team deliberately built toward where AI models were extrapolated to be in six months rather than where they currently stood — for instance skipping a JSON-output-parsing problem roughly 20 to 30 other YC companies were separately trying to solve, betting correctly that the next model generation would fix it.
  • The team chased the world's hardest coding benchmark before finding a product. Jha says he picked SWE-bench mainly to distract a frustrated team from pivoting every week, but becoming the world's top-ranked system on it with a four-person team became the technical foundation — including parallelized test-time compute and agent memory — that Emergent's product was later built on.
We just launched Paxel!
  • Paxel analyzes a builder's own coding transcripts to profile how they work. It scores users across five dimensions — steering, execution, engineering, product instinct and planning — surfacing patterns like their most-used prompt or how many agents they run in parallel, framed as "a mirror, not a grade."
  • All analysis runs locally, so a user's code never leaves their machine. The tool is described as a single command that takes 15 to 30 minutes to run before emailing the resulting builder profile, positioned as a way to surface skilled builders that a traditional resume would never reveal.
  • YC invites Startup School applicants to submit their Paxel results. The team frames this as a way to see "how you build, not just what you wrote," telling applicants who already submitted to go back and add their token, and stating it can only help, never hurt, an application.
Conductor CEO Charlie Holtz Walks Us Through His AI Coding Setup
  • He no longer writes code, only orchestrates agents. Charlie Holtz, co-founder of Conductor, says he manages multiple parallel coding-agent workspaces by voice, kicking off tasks with a gooseneck microphone and reviewing PRs rather than editing files himself; a manual-edit mode exists but is called "caveman mode" for how rarely it's used.
  • Deliberate "slop-free zones" stop AI from architecting the product. Conductor keeps parts of the codebase and docs, plus UI and interface decisions, off-limits to AI contribution and human-reviewed line by line, because he argues unattended AI code can spiral into a vicious cycle where bad code begets more bad code.
  • He spent $22,000 on tokens in a single month building Conductor, in July 2025, on a prior model generation, and now advocates "token maxing" — fast mode, high reasoning effort — while deliberately keeping lines of code minimal, since an established codebase can spiral out of control if line growth isn't controlled.
  • Code is becoming disposable; the prompt is the real asset. He argues code is now "sawdust" left over from describing what you want, so when new models ship you can simply rerun the same prompts to regenerate better code, likening this "malleable software" to modding a video game around a fixed core structure.
How to Build an AI-Native Services Company
  • The best AI-services markets share four specific traits. The speaker, presenting a YC playbook, argues founders should target work that is already outsourced (low trust), breakable into automatable steps (low judgment at the task level), genuinely hard (a high intelligence threshold), and regulated — since regulation raises the bar and the moat rather than just adding friction; examples cited include tax, audit, insurance, mortgages and healthcare.
  • Founding teams need domain fluency, model fluency, and operational rigor — the product is the operation. He points to General Legal Team, an AI-native law firm YC backed, whose founders combine law-firm experience at Cooley and Fenwick with technical leadership from CaseText and have built shift-based staffing to cut cycle times, calling variance in output the "existential problem" that causes customers to fire a vendor faster than slowness or price ever would.
  • New AI-services founders should deliberately cap their first pilot customers. He warns of an "early demand trap" where easy early sign-ups overwhelm delivery capacity before the product can scale, and advises pricing on outcomes or per-unit (per return, per claim, per loan) rather than cost-plus or straight-line undercutting, since services compete against the cost of labor, not other software.
  • The core financial bet is "AI operating leverage" pushing services margins toward software's. He argues traditional services firms cap out near 30% margins while AI-driven ones can approach 50%+ as the product lowers cost of goods sold (models, hosting, humans), on markets two to three times bigger than software's; he also argues buying an existing services business to bolt AI onto rarely works, since legacy hiring and performance expectations don't change with it.
Why Two IIT Engineers Turned Down $550K Jobs To Build A Startup
synopsis

Varun co-founded GigaML after turning down a quant-firm job offer; the company now runs AI customer-support agents for DoorDash, a top crypto exchange, and top telecom providers, pushing deflection rates it says can reach 90-95%, with a next product aimed at replacing the "forward deployed engineer" role in enterprise AI.

From EdTech rejection to a forced pivot. Varun and his IIT co-founder applied to YC with an LLM-based EdTech idea while he held a Stanford PhD offer. Harj Taggar dismissed the idea, telling them to use their LLM research on something else — advice Varun says left him panicked, sure the interview had gone badly. After talks with EdTech operators confirmed it was weak, they pivoted within a month.

A false start in fine-tuning, then a customer-driven pivot. They built an open-source fine-tuning product, topped Hugging Face benchmarks, and raised a $4 million seed — but concluded fine-tuning was a poor market, useful mainly for cost or for security buyers hard to sell to as engineers. Watching which use cases grew fastest among users, they saw support and coding leading, and pivoted; Zepto became their first customer.

Winning against scale. Unaware of well-funded rivals like Sierra, GigaML's eight-person team beat a roughly 400-person competitor for DoorDash's contract, aided by a YC introduction and a flawless three-month pilot. Varun reads this as proof product quality beats a sales team — a lesson reinforced by AI engineering leverage that he says lets GigaML run with a fraction of the staff a comparable company once needed.

  • YC's Harj rejected their EdTech idea, not their candidacy, and bet on the founders instead. Varun, GigaML's co-founder, says Harj told them "you guys are really good engineers, pick something else" without asking about their idea or traction, pushing them to abandon EdTech and pivot within a month of starting the batch based on their LLM research background rather than a specific pitch.
  • A GitHub usage pattern, not a market thesis, drove the pivot into customer support. After their initial fine-tuning product proved a bad market — good only for cutting inference cost or serving security-sensitive buyers that are hard for engineers to sell to — Varun says they noticed customer support and coding were the two use cases growing fastest among their fine-tuning customers, and Zepto became their first customer once they switched.
  • An eight-person team beat a roughly 400-person, well-funded rival for DoorDash's contract. Varun credits a YC-network "unfair advantage" (an introduction from Garry Tan) and a clean three-month pilot with no downtime, and says winning DoorDash proved to him that building a superior product beats building a sales team — a lesson he calls an "arbitrage" most competitors were missing.
  • Coding agents let GigaML run with roughly one-seventh the engineers it would otherwise need. Varun estimates the company would need six to seven times its current engineering headcount without tools like Claude Code, and says the deeper benefit is avoiding context-switching and context transfer between people, not just cost; the company's interview process still has candidates write code with AI, then edit it without AI, to confirm they understand it.
Inference, Diffusion, World Models, and More | YC Paper Club
synopsis

The inaugural YC Paper Club gathers around a hundred founders and researchers at YC's Pioneer space, and across five presentations the through-line is that classical ideas — speculation, factorized control, joint-embedding prediction, PAC-Bayes theory, regularization and ensembling — keep unlocking new capability once revisited at modern model scale, rather than requiring entirely new techniques.

Speculative speculative decoding. Stanford's Tanishk opens by reframing inference: rather than a cost or convenience factor, he argues that once a system's performance scales with how much it "thinks," tokens-per-second becomes the ceiling on delivered intelligence. Ordinary speculative decoding uses a small draft model to guess tokens that a large target model then verifies, but drafting and verification are sequentially dependent. His method predicts likely verification outcomes ahead of time, letting the next draft round start while the previous one is still being verified — hitting roughly 80-90% prediction accuracy and improving both latency and throughput sampling Llama 3 70B on four H100s.

Diffusion Model Predictive Control. Google DeepMind's Stannis, now leading a robotics world-modeling project, presents earlier work using diffusion models for both multi-step action proposals and multi-step dynamics models, factorized so they can be adapted independently. This lets a simulated agent adapt to novel reward functions or changed dynamics — such as a walker with a broken ankle — by re-adapting only the dynamics model, recovering most performance without retraining the action proposal, and it simplifies the planning algorithm to a simple sampler.

LeJEPA and the case for world models. Isaac Ward, from Yann LeCun's group, ties his talk to LeCun's reported $1.03 billion raise aimed largely at training world models. He presents LeJEPA, a joint-embedding predictive architecture that adds a single new regularization term ("SIGReg," enforcing Gaussian-distributed latent embeddings) to prevent the representational collapse that other world-model approaches fight with more complex tricks. He reports it runs about 50 times faster than competing world models, fits on a single GPU under 24GB of memory with only 15 million parameters, and — unlike model-free policies — can flag its own prediction error when conditions shift unexpectedly.

Why deep learning generalizes. QLabs' Ashe presents Andrew Gordon Wilson's argument that supposed mysteries of deep learning — overparameterization improving generalization, and "benign overfitting" where networks fit random noise yet still generalize on structured data — are largely explained by classical PAC-Bayes theory once compression is computed correctly. Larger models find more compressible, flatter minima, which tightens generalization bounds even at billion-parameter scale; the paper's implication is that better inductive biases, not new theory, are the lever for future sample efficiency.

Scaling laws when data, not compute, is the constraint. Closing the session, Ku presents work asking how to pre-train when compute is abundant but data is fixed — a regime he argues is approaching as internet text grows roughly 3% a year against 4-5x annual compute growth. Aggressive regularization and ensembling each produce clean power-law scaling with a measurable best-possible-loss asymptote, and combining them yields roughly a 5x data-efficiency win over standard recipes. He shows these gains survive compression: distilling an eight-model, 2.4-billion-parameter ensemble into one 300-million-parameter model retains about 83% of the improvement, and the same approach yields a roughly 17x data-efficiency win in a continued-pretraining setting constrained to math tokens.

  • Inference speed will become a capability ceiling, not just a cost lever. Presenting his "speculative speculative decoding" work, Stanford grad student Tanishk argues that once performance scales with amount of thinking, tokens-per-second is peak intelligence delivered; his method parallelizes normally-sequential drafting and verification by predicting verification outcomes about 80-90% of the time, winning on both latency and throughput sampling Llama 3 70B on 4 H100s.
  • Factoring the action proposal from the dynamics model lets a robot policy adapt at runtime. Google DeepMind's Stannis presents Diffusion Model Predictive Control, where multi-step diffusion models for action proposals and dynamics reduce compounding errors and simplify planning; he shows a simulated walker with a broken ankle recovers most of its performance just by re-adapting the dynamics model, without retraining the action proposal.
  • A single new regularizer lets a world model avoid representational collapse with one hyperparameter. Isaac Ward, from Yann LeCun's group (whose $1.03 billion raise centers on world models), presents "LeJEPA," which adds a "SIGReg" term enforcing Gaussian-distributed latent embeddings; he reports it runs roughly 50 times faster than competing world models on a single GPU under 24GB of memory with just 15 million parameters, and can flag its own prediction errors when conditions shift.
  • Ensembling and distillation, not bigger single models, are the efficient path when data — not compute — is the constraint. Presenting a paper co-led with Suhas and Percy Liang plus another collaborator, Ku shows that regularized and ensembled pre-training recipes follow clean power laws with measurable best-possible-loss asymptotes; a joint recipe yields roughly a 5x data-efficiency win, and distilling an eight-model, 2.4-billion-parameter ensemble into one 300-million-parameter model retains about 83% of the gain.
Inside YC's AI Playbook
synopsis

YC general partner Pete Koomen, who built the firm's internal agent infrastructure, joins Garry Tan to explain how YC turned itself into an AI-native organization, arriving at the claim that building "superintelligence inside a company" requires no single breakthrough — just a shared context layer, an ever-growing registry of reusable skills, and a culture radically transparent and trusting enough to let agents use it all.

From a finance workflow to a database unlock. The project began about a year ago when Koomen and engineers, frustrated by the slow loop of finance staff describing workflows for engineers to hard-code, tried giving agents direct tools instead. The turning point was giving agents read-only SQL access to YC's single Postgres database, which holds every company, founder and financial record; Koomen argues this collapsed the cost of asking complex questions enough to trigger a Jevons-paradox-style surge in how many people bothered to ask them at all, since staff no longer had to queue behind engineers or data teams to get answers.

A registry that grew from 20 tools to 350. As more teams built on the shared agent loop, YC's internal tool registry expanded roughly seventeen-fold, and a "resolver" pattern — an agents.md-style entry point linking to markdown skills — let agents discover and reuse capabilities instead of duplicating them, checked against redundancy with a "dry and MECE" meta-skill Tan built.

Transparency as the safety mechanism. Rather than restrict access, YC broadcasts every internal agent conversation to Slack by default, a contested decision Koomen says paid off: employees learned techniques by watching each other, and the visibility itself discouraged misuse of the broad context access agents need to be powerful — a trade-off he argues depends on an egalitarian, trust-by-default culture more common at small, aligned startups than at legacy organizations.

From one skill to organizational superintelligence. A partner's handwritten skill for writing founders' "two-sentence descriptions" improved after colleagues fed a group office-hours transcript back into it, until Koomen says it wrote pitches better than any partner individually — the concrete mechanism, he and Tan argue, by which composing many such improved skills builds a genuine shared organizational brain.

A fork in AI's future. The conversation closes on Koomen's "Horseless Carriages" essay: that AI-native software should let an agent wrap deterministic tools, not the reverse, shifting control from developer to user. Tan extends this into a broader warning, drawing a parallel to the mainframe-to-personal-computer revolution: the next two years will decide whether AI ends up centrally controlled and locked down, or personally programmable the way early hobbyist computing was — a choice he argues falls to the founders building these systems now.

  • A single shared database, not better tools, was YC's real unlock for internal agents. Partner Pete Koomen says YC runs on its own software sitting on one Postgres database covering every company, founder and financial record, so an agent with read-only SQL access could answer arbitrary questions; he argues this collapsed the friction of cross-team requests enough to trigger a Jevons-paradox-style explosion in the number and complexity of questions people bothered to ask.
  • A tool registry grew from about 20 tools to over 350 as teams kept adding their own. Koomen describes YC's internal harness evolving from a simple agent loop into a shared registry that any team can extend, and says the key move was building a "resolver" — an agents.md-style entry point linking to markdown skills — so agents could discover and reuse capabilities instead of duplicating them, checked for redundancy with what Garry Tan calls a "dry and MECE" meta-skill.
  • YC deliberately broadcasts every internal agent conversation to Slack by default. Koomen says this transparency, chosen despite internal debate, let employees learn techniques by watching others use agents and created a social check that made it safer to give agents broad access to sensitive context — a trade-off he argues requires an "egalitarian, trust by default" culture that works best in small, aligned organizations.
  • A single partner's handwritten skill for writing "two-sentence descriptions" became better than any individual partner at YC. After other partners fed a group office-hours transcript back to the agent to refine the skill, Koomen says it now writes better two-sentence founder pitches than he does personally, illustrating what he and Tan call building "superintelligence inside a company": composing many individually improved skills into a shared organizational capability.
How The Best Companies Defend Against Mediocrity And Rot
synopsis

Eric Ries, author of "The Lean Startup" and the forthcoming "The Uncorruptable," argues that companies don't decay because corruption is an inevitable cost of scale, but because founders unknowingly adopt specific, changeable legal structures — standard Delaware C-corp shareholder primacy — that make their mission disposable the moment it becomes valuable enough to be worth taking over; the fix, he argues, is structural choices made early, not good intentions sustained forever.

The trap that motivated the book. Ries describes coaching a founder building AI-plus-bioscience technology who wanted assurance his company would never be misused, only to discover his standard Delaware C-corp charter already legally obligated directors to maximize shareholder value regardless of his intentions. Ries frames the deeper problem as an industry-wide blind spot: success makes an organization a bigger target, not a safer one, and "the professor" had unknowingly signed away his ability to protect what he'd built.

Shareholder primacy is invented history, not natural law. Ries traces a lineage from 19th-century corporate charters, which specified a purpose a board had a fiduciary duty to defend (illustrated by a fight over the Erie Canal Company), through Delaware's 1899 general-incorporation law, to a small group of judges and academics in the 1960s-70s who reinterpreted "any lawful activity" as implying shareholder-value maximization — a standard, he stresses, never enacted by legislation or vote, yet enforced by courts as if it were.

Founders keep losing control despite succeeding. He cites Twilio's Jeff Lawson, removed 199 days after his dual-class control sunset expired even as revenue kept growing, and Sol Price, locked out of FedMart in 1975 after 20 years building it; FedMart went bankrupt within seven years under new "best practice" ownership, while Price went on to found what became Costco — which Ries holds up as evidence a differently governed company can both protect its mission and outperform.

Why standard "best practices" fail, and what works instead. Ries argues independent board directors, despite having no equity stake, have a financial incentive to be seen as pro-investor since investors recommend them for future seats — meaning a classic two-VC/two-founder/one-independent board is effectively investor-controlled. He points to data showing companies using a separate structure instead — a nonprofit or trust of outside trustees appointing for-profit directors, as at Novo Nordisk and Zeiss — are six times more likely to survive to year fifty.

The mechanism proven, then applied to AI. Ries recounts Novo Nordisk's trustees blocking a lucrative 2000s merger because it wasn't necessary for survival; the rival firm that merged instead later had its R&D cancelled after acquisition by Merck, while Novo Nordisk kept funding an unproven GLP-1 program for over a decade to a $600 billion valuation. He closes by pointing to Anthropic's long-term benefit trust, which he helped design, as a modern version of the same structure — crediting it, alongside a genuine safety mission, for the company's willingness to turn down a $200 million contract, and recommending a public benefit corporation filing as the cheapest first step any founder can take today.

  • Shareholder primacy is a recent legal invention, not a law anyone ever passed. Eric Ries, author of the forthcoming "The Uncorruptable," traces it to a small group of academics and judges in the 1960s-70s who reinterpreted "any lawful activity" charters as requiring shareholder-value maximization — a norm he says has never been subject to legislation or referendum, yet is treated as binding by courts, as when Twitter's board was compelled to sue to complete Elon Musk's takeover.
  • Founders keep losing companies they built even while succeeding by every normal measure. Ries cites Twilio's Jeff Lawson, ousted 199 days after his dual-class control sunset expired despite revenue growth since IPO, and Sol Price, locked out of FedMart in 1975 by a new board after 20 years building it; FedMart went bankrupt within seven years of adopting standard shareholder-value practices, while Price's next venture became Costco.
  • Independent board directors don't solve investor control — they just make it look balanced. Ries argues independent directors have no equity stake in a company's mission but do have a financial incentive to be seen as pro-investor, since investors recommend them for future board seats, making the classic two-VC/two-founder/one-independent board effectively investor-controlled; he cites data that companies using a separate nonprofit-trustee structure instead are six times more likely to survive to year fifty.
  • A nonprofit trustee board can preserve value the market would have destroyed. Ries recounts Novo Nordisk's foundation trustees blocking a lucrative 2000s merger because it wasn't necessary for the company's survival — the rival company that merged instead had its R&D cancelled after being acquired by Merck — allowing Novo Nordisk to keep funding an unproven GLP-1 program for over a decade to a later $600 billion valuation; he points to Anthropic's similar long-term benefit trust as enabling its refusal of a $200 million contract.
OpenAI: $2M in tokens to every YC company in the spring and summer batches.
  • OpenAI is investing $2 million in tokens, not cash, into every spring and summer 2026 YC company. Garry Tan explains the money comes via an uncapped SAFE, effectively pricing the investment at the company's future Series A valuation but committing it at the earliest stage, and can be spent on Codex or the OpenAI API.
  • The deal targets founders "token maxing" through software-factory patterns. Tan describes dispatching many agents to burn large volumes of tokens as a way to reach what would have been 18 months of engineering and Series-A-level product polish in a fraction of the time, and says YC observed its best current companies already spending heavily on tokens this early in their life cycle.
  • YC extended a special application window since the summer batch deadline had already passed. Tan says the offer, developed together with Sam Altman, is being run as an experiment for just this spring and summer batch, with applications due by Memorial Day weekend (May 25) and decisions promised by June 5.
Zepto: How Two 17-Year-Olds Built India's Largest Seller Of Fruits and Vegetables
synopsis

Aadit Palicha, who co-founded Zepto with Kaivalya Vohra at 17, describes a company that has grown from a neighborhood WhatsApp grocery chat into India's largest platform seller of fruits and vegetables and a 200,000-plus-employee logistics operation, with a stated goal of becoming India's homegrown version of Amazon by building urban grocery infrastructure for the country's next 40-50 cities.

A pivot driven by one data point. Stuck in Mumbai during COVID instead of starting at Stanford, Palicha and Vohra began delivering for neighbors via WhatsApp under the name Kirana Cart, sourcing from existing stores. Dissatisfied customers convinced them the model couldn't control delivery speed or selection, so they set up a mini-warehouse — the first inside a co-founder's apartment — and found that neighborhood generating three to four times the order volume of areas still served the old way, the signal that triggered the pivot into what became Zepto.

Working backward from an extreme ideal. Rather than starting from what a warehouse model made feasible, Palicha says they designed toward the most extreme customer experience imaginable, inspired by Airbnb's "seven-star" thinking, arriving at 10-minute delivery. He argues the resulting demand and throughput per warehouse lowered costs as a byproduct, rather than cost-cutting driving the experience.

A deliberately delayed commitment. Palicha waited roughly eight to nine months, until the business reached about 10,000 orders a day and a 60-70 crore run rate with an investor term sheet in hand, before fully committing instead of returning to Stanford — proof of traction first, then the leap.

Scaling with AI. Palicha says machine-learning forecasting now runs warehouse replenishment for millions of units daily without humans in the loop, GenAI-driven ad tools grew Zepto's advertising business, and automation let the company cut nearly all software spending while running its corporate functions with roughly 500 engineers.

  • Zepto's founding pivot came from data, not strategy: one dark-store neighborhood outperformed the rest 3-4x. Aadit Palicha says he and Kaivalya Vohra started at 17 delivering groceries via a WhatsApp group in Mumbai during COVID, under the name Kirana Cart, but only switched to running their own mini-warehouses — the first literally inside a co-founder's apartment — after seeing that neighborhood's order volume dwarf areas still served by doorstep delivery from existing stores.
  • They designed backward from an extreme ideal experience rather than forward from what was operationally feasible. Palicha credits a discussion of Airbnb's "seven-star" thinking for the approach behind 10-minute delivery, and argues that nailing customer experience — not cost-cutting — created the demand and throughput per warehouse that then made costs low, concluding "customer delight is where financial value starts."
  • He delayed dropping out of Stanford for about eight to nine months until reaching early product-market-fit signals. Palicha says he waited until the business hit roughly 10,000 orders a day and a run rate of 60-70 crore, plus secured a term sheet, before committing full-time — advising founders to have proof a business is working before taking that kind of risk, not before.
  • AI operations work has let Zepto's supply chain and corporate teams run with far fewer people. Palicha says machine-learning forecasting now runs dark-store replenishment for millions of units a day without humans in the loop, replacing forecasts that used to take teams days, while GenAI-driven ad-keyword tools boosted advertising revenue and internal automation let the company cut nearly all SaaS and outsourced-service spending with a corporate team of about 500 engineers plus 150 in data, product and design.
Thanks for a great time, India 🇮🇳
  • YC says the India event drew over 25,000 applications. A speaker tells the crowd that India's AI ecosystem will be defined by the people in the room, not by the prior generation.
Paul Graham, Founder of Y Combinator, Live from Stockholm
  • Every field concentrates in one place, and the historical answer is always to go there. Paul Graham compares Silicon Valley today to Paris for painting in 1870 or Göttingen for math in 1900, arguing the talent pool at a center improves in two dimensions — better people and more of them — which he says produces disproportionately valuable serendipitous meetings that he cannot fully explain but has observed repeatedly in biographies of accomplished people.
  • Silicon Valley investors decide faster because competition punishes hesitation, and it doesn't hurt their returns. Graham argues the more confident an investor is about an opportunity, the less time they can afford to wait, illustrated by a Boston VC firm that faxed Dropbox a blank-valuation term sheet only after learning Sequoia was interested — too late, since Dropbox went with Sequoia and became the first YC company to go public, in 2018.
  • Comparing yourself to visible "big fish" resets ambition from impossible to merely hard. Graham says moving to a big pond lets founders measure themselves against known peers like Brian Chesky or Sam Altman and conclude they aren't a different species, just people who worked exceptionally hard — turning a fogged-in, seemingly unreachable summit into "a high but definite threshold."
  • Founders should go to Silicon Valley, ideally via YC, and then return home — even though data shows returners do worse on paper. Graham argues going and coming back is the best way to help a hub like Stockholm, bringing back money, imported culture and a stronger startup, but acknowledges YC data shows founders who return home are only about half as likely to become unicorns as those who stay — a gap he attributes partly to selection bias and to Bay Area startups raising at higher valuations, not necessarily performing better.
Tokenmaxxing: How Top Builders Use AI To Do The Work Of 400 Engineers
synopsis

After a multi-year hiatus from coding, Garry Tan describes returning to building and shipping hundreds of thousands of lines of code while running YC full-time, arriving at the argument that "token maxing" — spending liberally on AI compute the way one would on rent in a city that creates serendipity — is now the defining lever for builders, and that the deeper choice ahead is whether people control their own AI tools and prompts or let centrally controlled products control them.

A blogging platform rebuilt three times shows the cost collapse. Tan traces his project, eventually called Gary's List, back through Posterous (2008: $4 million, six to seven people, about a year and a half) and a 2013 rewrite (roughly $100,000, two people, three months) to a 2026 version built for about $200 and five days using Claude Code, this time with full agentic research and retrieval capability the earlier versions lacked entirely.

"Boiling the ocean" reframes economizing as a mistake. Because an agent can cross-reference twenty sources as cheaply as one, Tan argues builders should stop rationing research or code depth the way limited human effort once forced them to, and predicts this token-maxing mindset will spread from coding into every kind of knowledge work, not eliminating people but requiring them to supply the agency and judgment behind each request.

G Stack crystallized into "thin harness, fat skills." Tan describes discovering that markdown-based skills — a "CEO" review for ambition, plan-and-engineering review, developer review, and a Playwright-based QA skill — should carry the judgment and checklists, while the underlying agent harness stays minimal; deterministic code, he argues, is too brittle for cases requiring understanding of intent, and skipping 80-90% test coverage produces output he calls "10x worse than human-written code."

A contested claim, clarified. After public criticism of his "100x" productivity claim, Tan says a stripped, standardized measure of logical lines of code showed he was actually producing roughly 400 times his 2013 output, directing around fifteen agents simultaneously, even though the code he personally typed fell about 70% from that baseline — a nuance, he says, that got lost in the online argument.

The conversation closes on stakes beyond productivity: Tan frames the choice between personally controlled AI, with one's own prompts, data, and integrations, and corporate-controlled AI as comparable to the personal-computer revolution, arguing that not writing your own prompts leaves you "below the API line" for someone else's product decisions.

  • Garry Tan rebuilt the same blog platform three times, and the cost collapsed by roughly 20,000x. He says the 2008 version (Posterous) took $4 million, six or seven people and about a year and a half; a 2013 rewrite took roughly $100,000, two people and three months; the 2026 version, built with a Claude Code Max subscription, cost about $200 and five days while adding full agentic retrieval and research capability the earlier versions never had.
  • "Boiling the ocean" — paying for exhaustive completeness — is now cheap enough to be standard practice. Tan argues that because an agent can cross-reference twenty sources as easily as one, builders should stop economizing on research or code depth the way a human effort-budget would force them to, calling this "token maxing" and arguing it will spread from coding into every kind of knowledge work.
  • A "thin harness, fat skills" philosophy puts judgment in markdown, not code. Tan describes building G Stack around markdown skills — a "CEO" review for ambition, a plan-and-engineering review, a developer review, and browser-based QA — while keeping the underlying agent harness minimal, arguing that anything requiring human-style judgment belongs in plain-language markdown rather than brittle deterministic code, and that skipping 80-90% test coverage produces output "10x worse than human-written code."
  • Measuring logical lines of code, Tan found he was producing about 400 times his 2013 output, directing roughly 15 agents at once, even though the code he personally typed dropped about 70% from his 2013 baseline — a distinction he says got lost when his "100x" claim drew online criticism. He frames the larger stakes as builders needing to control their own prompts and tools rather than depend on centrally controlled AI products, calling it "the defining question" of the moment.
Startup School Paris
  • YC is hosting a one-day Startup School Paris on June 29th. Builders across France and Europe will hear from founders of companies including DataDog, Supabase, and Amie, plus get direct access to YC partners and alumni.
Harshil Mathur: AI Is Compressing Every Moat
synopsis

Razorpay co-founder Harshil Mathur, an accidental fintech founder who stumbled into payments while building an unrelated side project, ends by arguing that AI is now dissolving the capital, infrastructure and build-speed moats that used to separate incumbents from startups, leaving only two real differentiators: how fast a company decides what to build, and whether its founder has the trust and conviction to keep steering it.

An accidental start, then a hard-won regulatory moat. Mathur got into payments only because accepting money for his own side project was needlessly hard in India; a pivot from education institutes (which didn't actually care about digital collections) to fellow startups gave Razorpay its real customers. Getting licensed then took a full year past YC before their first live transaction — a delay he now credits as a moat, since every future competitor must clear the same slow approval process.

A crisis that hardened a trust policy. When Razorpay's bank partner abruptly cut off about 50 live merchants two weeks after demo day, the team personally called and absorbed abuse from every affected customer rather than going silent, regaining a partner within days. Mathur says this is why Razorpay still refuses to let AI replace customer support today, treating it as a trust channel rather than a problem to automate away.

Deliberate inefficiency as strategy. After raising an $11 million Series A, Razorpay kept burn under $200,000 a month and banked the rest, earning more in interest than it spent — a choice that irritated its investor but reflected Mathur's view that B2B value is paid for daily, not grown through subsidized acquisition.

A bet on UPI, and the moats AI is erasing. Because Razorpay had "nothing to lose," it went live on India's unproven UPI system months before major banks did, capturing a six-month window after 2016's demonetization that won it clients like Zomato and Swiggy before rivals could respond. Mathur closes by warning founders that AI won't make entrepreneurship easier, only building faster — the remaining test is finding a problem worth a decade of a founder's attention.

  • Regulatory friction that nearly killed Razorpay's launch became its deepest moat. Harshil Mathur says it took a full year after joining YC just to complete their first live transaction, since payment licensing required certifications and approvals before any transaction could occur; he argues this hurdle is actually fair because every later competitor must clear the same year-long process, which keeps the field of entrants small in a way ordinary tech products can't replicate.
  • A banking-partner crisis two weeks after demo day became a lesson in trust that shaped a permanent AI policy. When Razorpay's enabling bank abruptly cut off around 50 live merchants over one complaint, Mathur says the team personally called every affected customer, absorbing abuse rather than going silent, and regained a live partner within days; he cites this as why Razorpay still refuses to let AI replace customer support, even while using it elsewhere, because he sees support as a trust channel rather than just a problem-solving function.
  • Razorpay deliberately stayed capital-inefficient by choice, banking Series A funds instead of burning them. After raising roughly $11 million, Mathur says the company kept monthly burn under $200,000 and earned more in bank interest than it spent, angering an investor who expected it to burn faster; he argues B2B economics are inherently "logical" — a business pays only for value delivered today, unlike consumer models that spend to acquire and monetize later.
  • A calculated early bet on India's then-unproven UPI system, made because the company had nothing to lose, created a six-month competitive window. Mathur says Razorpay went live on UPI months before India's largest banks did, so when demonetization hit in November 2016 and demand surged, it was the only payment gateway ready — winning clients like Zomato, Swiggy and BookMyShow before rivals caught up; he extends this into a broader claim that AI is now compressing capital and infrastructure moats industry-wide, leaving execution speed and the willingness to reinvent proactively, rather than wait to "respond," as the only differentiator left.
Inference Chips for Agent Workflows
  • Current AI chips are poorly suited to how agents actually run. YC says this causes GPUs to hit only 30–40% peak utilization on agentic workloads, because agents loop, branch, and backtrack across dozens of steps, bouncing between memory-bound model calls, IO-bound tool use, and CPU-bound orchestration — a fundamentally different hardware problem than simple prompt-in, response-out inference.
  • Purpose-built silicon for the agent loop itself is still missing. YC points to Nvidia's reported $20 billion acquisition of Groq and Google's inference-specific TPU v7 as evidence the shift toward specialized hardware is underway, but argues the real advantage is the compiler, not the chip — fast context switching between models, native speculative decoding, and memory built for KV caches that persist across an entire execution graph.
AI-Native Discovery Engines
  • Scientific discovery is shifting from AI copilots to closed discovery loops. YC argues this is already happening in drug discovery, material science, and protein engineering, where models propose candidate molecules, automated labs synthesize and test them, and results feed back to iteratively improve the next candidate; it predicts the most impactful companies won't just sell research copilots but will be full AI-native discovery engines.
The AI Operating System for Companies
  • The best AI-native companies make their whole operation queryable by AI. YC argues this turns decision-making into a closed loop — the system monitors what's happening, compares it to what should be happening, and adjusts — citing teams that cut sprint time in half and shipped 10x as much after recording every meeting and tracking every ticket and customer interaction.
  • Building this today requires brutal custom integration work across tools. YC points to Slack, Linear, GitHub, Notion, and call recordings as the kind of systems currently stitched together with custom glue code, with no single product connecting it all into one AI layer; it wants to back the connective layer that makes a company legible to AI by default, rather than another one-off patchwork.
SaaS Challengers
  • AI has collapsed the cost of producing software by 100x or more. YC argues this erases the code-volume moat that protected legacy SaaS incumbents, framing the recent hit to software market caps as bad for incumbents but good for startups, since decades-old codebases once considered untouchable are now vulnerable to cloning, bundling, or open-source replacement.
  • YC is pushing founders toward bigger targets than typical product-management tools. It names chip design software, ERPs, industrial control systems, and supply chain management as the next frontier, framing it as a repeat of the shift from on-premise to cloud: the next generation of great software companies will replace legacy SaaS with AI-native software.
Industrial Capabilities in Space
  • Star Cloud's Adi Oltean wants YC to fund lunar industrial capabilities. He describes starting with extracting raw materials like silicon, aluminum, iron, and titanium from lunar regolith via electrolysis, then 3D printing complex structures from the molten material — which he says could be more efficient than on Earth due to the lack of structural supports needed.
Software for Agents
  • Every major software category needs to be rebuilt for AI agents. YC argues agents need machine-readable interfaces like APIs, MCPs, and CLIs, plus thorough documentation to discover and use tools without a human in the loop, replacing the visual forms and dashboards built for people — and predicts this rebuild will come from agent-first startups rather than incumbents bolting on agent support.
Hardware Supply Chain
  • US hardware moves far slower than China's because of iteration speed. YC contrasts Shenzhen, where a team can go from design to a physical part in a day, with the US, where the same loop takes weeks, attributing China's edge to dense supplier networks and tight coordination between design and production.
  • YC wants to fund startups that make US hardware iteration dramatically faster. It points to a startup already building faster turnaround from design to manufactured mechanical part as an early example of the kind of missing infrastructure it's looking for.
Recursion Is The Next Scaling Law In AI
synopsis

By the end of this Decoded episode, Francois Chopard and the host arrive at a shared position: recursion, not scale, is the missing ingredient in today's LLMs, and the biggest gains will come from combining the two rather than choosing between them.

Why feedforward transformers can't reason past their depth. Chopard traces the argument to a structural difference between transformers and RNNs: transformers process a whole sequence in one parallel, feedforward pass with no compression across time, while RNNs iterate on a compressed hidden state but were historically crippled by backprop-through-time — vanishing and exploding gradients, and activations that had to be stored at every step. He argues certain problems are provably "incompressible": comparison sorting has a proven n·log(n) lower bound on steps, and Sudoku, mazes and rolling sums are similar. A transformer with fewer layers than the required number of sequential steps simply cannot solve them in one shot. Chain-of-thought and tool-calling let LLMs simulate a Turing machine at test time, but only within the bounds of human-demonstrated traces — an LLM shown only bubble sort, he says, could not discover merge sort.

HRM proves recursion works at tiny scale. The Hierarchical Reasoning Model — 27 million parameters, no pretraining, trained on roughly 1,000 ARC-AGI puzzles — scored around 70% on ARC-1 when OpenAI's o3 scored zero, using two recursive modules (a low-frequency and high-frequency network) plus an outer refinement loop, trained with a truncated, deep-equilibrium-style backprop rather than full backprop-through-time.

TRM strips it down and improves on it. A follow-up paper by a researcher Chopard calls Alexia collapses HRM's two networks into one, cuts the transformer to a single layer, and backpropagates through one full recursion step instead of truncating — shrinking the model to 7 million parameters while raising the ARC-1 score to 87%. Ablations Chopard cites credit the outer refinement loop, not the two-network hierarchy, as the real source of the gain.

Where recursion goes next. Both models are task-specific, trained only for the puzzle type they solve, unlike general-purpose LLMs. Chopard's forecast is that combining a large pretrained model's embedding space with a small recursive reasoner operating inside it — something he believes may already exist in part inside Gemini — is going to "take off."

  • Transformers trade recursive reasoning for parallel training speed. Chopard argues that unlike RNNs, which iterate on a compressed hidden state across time steps, an LLM computes in one feedforward pass with no compression in the time direction — every decode re-processes the full context. RNNs paid for their recursion with backprop-through-time, which caused vanishing and exploding gradients as models or sequences grew.
  • Some problems are provably incompressible, unsolvable in one forward pass. He cites comparison sorting's known n·log(n)-step lower bound, plus Sudoku, mazes and rolling sums, arguing a transformer with fewer layers than the required steps cannot solve them. Chain-of-thought and tool-calling can simulate a Turing machine at test time, but only within human-demonstrated traces — an LLM taught only bubble sort, he says, could not discover merge sort on its own.
  • A tiny recursive model outperformed giant pretrained LLMs on ARC-AGI. He credits the Hierarchical Reasoning Model — a 27-million-parameter model with no pretraining, trained on roughly 1,000 ARC-AGI tasks — with scoring about 70% on ARC-1 versus OpenAI's o3 scoring zero at the time. The follow-up Tiny Recursive Model, by a researcher he calls Alexia, shrank it to 7 million parameters by collapsing HRM's two networks into one, and pushed the score to 87%.
  • The outer refinement loop, not the two-network design, drives the gain. Chopard says a researcher at Francois Chollet's company ran scaling ablations showing this repeated outer loop is the main source of HRM and TRM's performance, which is why TRM kept and simplified around it while discarding most of the rest. He expects the next leap to come from combining this recursion with giant pretrained LLMs rather than treating either as a substitute for the other, since today's recursive models are trained per task, not general-purpose.
Startups That Sell to the Biggest Companies in the World
  • AI has erased the barriers to selling to the world's largest companies. YC argues enterprise leaders now actively seek teams that can apply AI to their problems, coding agents let a two-to-three person team ship nuanced products to large companies in months rather than years, and those leaders now understand what to build in-house versus outsource — making it common for a YC startup's first customer to be one of the largest companies in the world. This, YC says, kills the old model of startups operating in stealth for years to reach feature parity with an incumbent before launching.
Supply Chain 2.0 for Semiconductors
  • Semiconductor supply chains are still run on spreadsheets and calls. YC notes a single advanced AI chip takes 1,400 manufacturing steps across a dozen countries over five months, and cites 2021, when a $300 chip held up a $50,000 car and left $200 billion in vehicles unbuilt, as proof that companies see their direct suppliers but have no visibility into second- and third-tier ones.
  • The bottleneck has only gotten worse. YC says Nvidia has locked up over 60% of TSMC's advanced packaging capacity, high-bandwidth memory is booked through 2026, export controls change quarterly, and the CHIPS Act is standing up new fabs in Arizona, Texas, Ohio, and New York that each need a supply chain built from scratch.
  • This tooling doesn't exist yet, and building it needs deep technical knowledge. YC says real-time allocation tracking, multi-tier risk monitoring, and export compliance all require understanding wafer allocation and packaging constraints at a deep level — which is why it sees this as a startup opportunity rather than a feature bolted onto SAP.
Dynamic Software Interfaces
  • Coding agents now let ordinary users become their own "forward-deployed engineers." YC notes that before AI, nearly all software shipped one interface for everyone — Netflix looks the same for every user, just with different imagery — with deep per-customer customization limited to enterprise software built by human forward-deployed engineers, and argues users can now radically customize interfaces themselves.
  • This implies rethinking how software gets delivered. YC raises open questions like whether companies will need to ship source code instead of packaged binaries, and whether users' agents should be able to modify only front-end elements or also middleware on the fly.
YC Paper Club
  • YC is launching a Paper Club to keep builders and researchers current on frontier AI. Framed around how hard it is even for a PhD student to keep up, the group will meet every few weeks at YC's Mountain View office to present and discuss papers, followed by an off-the-record dinner; the first cohort caps under 100 people and meets May 20.
Demis Hassabis: Agents, AGI & The Next Big Scientific Breakthrough
synopsis

By the end of the conversation, Demis Hassabis lands on a specific bet: the current paradigm — pretraining, RLHF, chain-of-thought — will very likely form the core of AGI, which he expects around 2030, but only once continual learning, long-term reasoning and memory are solved, a gap he rates as even odds between needing incremental scaling versus one or two genuinely new ideas.

Memory and continual learning are still duct tape. Hassabis, who studied hippocampal memory consolidation for his PhD, says today's systems fake continuity by stuffing everything into an ever-larger context window rather than truly learning, and traces DeepMind's alternative approach back to the 2013 Atari-playing DQN's experience replay, itself borrowed from how sleep consolidates memory in the brain.

Reasoning is brute force, and it shows. He describes watching Gemini play chess and seeing its own thinking trace identify a losing move as a blunder, then play it anyway — a lack of introspection into its own reasoning that he thinks explains "jagged intelligence": the same model can solve gold-medal Olympiad problems yet fail simple arithmetic.

Agents are early, and the marker for arrival is a hit game, not a benchmark. DeepMind's own history — Atari, AlphaGo, AlphaStar — is agent research, and Hassabis calls agents the necessary path to AGI. But he says no AI-built game has topped the App Store the way a studio hit would, and expects that within 6 to 12 months; individual builders working at something like 1000x their old output, he predicts, will appear before agents work fully autonomously.

Science is where he expects the clearest payoff. Isomorphic Labs is extending AlphaFold's approach into drug-discovery chemistry, with announcements he says are coming soon, and a full "virtual cell" simulation is roughly a decade out — DeepMind is starting with a self-contained cell nucleus, blocked less by modeling than by the lack of imaging technology that can capture a live cell at nanometer resolution without killing it. His advice to founders: look for AlphaFold's recipe — a massive combinatorial search space, a clear objective function, and enough data or simulation to generate synthetic training data — and pair deep AI expertise with a hard science domain, one of the few bets he considers safe from the next foundation-model update. He adds that such a venture started today is a roughly ten-year journey, one his own AGI timeline lands in the middle of, and says builders should plan for that.

  • Hassabis expects AGI soon, but flags one or two open unknowns. His personal timeline is around 2030; he says continual learning, long-term reasoning and some aspects of memory remain unsolved, and puts it at "50/50" whether closing those gaps needs one or two genuinely new ideas or just incremental scaling of what already works — DeepMind is pursuing both bets at once.
  • Today's reasoning models are only "fairly brute force," producing jagged intelligence. Watching Gemini play chess, Hassabis says its own thinking trace will identify a move as a blunder and then play it anyway — evidence, he argues, that models lack introspection into their own reasoning, which is why the same system can solve IMO gold-medal problems yet still make elementary math errors.
  • Agents haven't truly arrived until a vibe-coded game tops the charts. Hassabis says no AI-built game has hit the App Store charts the way a studio-made hit would, and expects that to change in the next 6 to 12 months; he predicts individual builders working at roughly 1000x their prior output will appear before agents operate fully autonomously.
  • The AlphaFold pattern: combinatorial search, a clear objective, plenty of data. Hassabis says that formula — a massive combinatorial search space, a clear objective function to hill-climb, and enough data or simulation to generate synthetic training data — drove both AlphaGo and AlphaFold, and advises founders to pair deep AI expertise with a hard science domain like materials or medicine as one of the few bets defensible against the next foundation-model update.
Electronics in Space
  • Space-optimized inference chips are an emerging startup opportunity. Philip Johnston, co-founder and CEO of Starcloud (building data centers in space), argues reusable rockets from SpaceX and Stoke Space will drive a huge increase in orbital compute capacity, creating demand for chips tuned for mass, thermal and radiation constraints; he's looking to hear from chip designers with experience at SpaceX or Nvidia.
Counter-Swarm Defense
  • A drone swarm reportedly destroyed an AWS data center unopposed. He says a swarm of cheap Iranian drones took out the facility last month with nobody stopping it, and warns that a coordinated swarm of a thousand drones — far larger than the single hobby drones most counter-drone systems are built to handle — would be even harder to stop.
  • The cost math today overwhelmingly favors attackers, not defenders. He points to a $3 million Patriot missile intercepting a $500 FPV drone as the current exchange rate, and argues restoring that cost advantage to the defense side is the real problem to solve.
  • YC wants to fund the counter-swarm stack as software, not weapons. He lists interceptors that neutralize dozens of drones at once, sensor-fusion software giving a single real-time picture, and non-kinetic tools like rotor-fouling aerosols and entangling streamers — arguing that with radio jamming becoming obsolete, the winning companies will resemble Cloudflare more than Raytheon.
Company Brain
  • AI automation of companies is now blocked by scattered internal knowledge, not model quality. The speaker argues every business needs a "company brain" — a system that extracts tacit know-how from emails, Slack, support tickets and databases into a living, current "skills file" so AI agents can execute tasks like refunds or pricing exceptions safely and consistently.
AI-Personalized Medicine
  • Falling diagnostic and gene-therapy costs, paired with agent harnesses, will enable personalized medicine at scale. The speaker says genome-sequencing costs have fallen faster than Moore's Law and that N-of-1 mRNA-based therapies plus greater FDA openness are emerging, arguing agents like Claude Code can combine genomic, EHR and wearable data into individualized treatment suggestions.
AI-Native Service Companies
  • AI-native companies that sell the finished service, not a software tool, are the next wave. The speaker contrasts 2023–2025 "AI co-pilot" startups with a new category that performs the work itself — citing insurance brokerage, accounting, tax, audit and healthcare administration — arguing total services spend dwarfs software spend and is easier to disrupt because much of it is already outsourced.
AI for Low-Pesticide Agriculture
  • Farmers are trapped in a worsening chemical treadmill. The narrator argues pesticide resistance keeps evolving, the pipeline for new chemicals has gotten slower and more expensive, and farmers must keep spraying more for diminishing results even as costs rise and margins fall, because failing to spray risks crop loss and food-price shocks.
  • Three technologies converging at once make the problem newly solvable. He points to cheap sensors and cameras giving AI real-time weed/pest identification, robotics precise enough to treat individual plants instead of whole fields, and biological alternatives (microbes, peptides, RNA-based tools, engineered self-defending plants) capable of replacing whole classes of synthetic chemicals.
  • This is framed as a generational investment opportunity for YC. The narrator predicts adoption will be "explosive" rather than slow because a company that cuts pesticide use by 90% while increasing yields would be attractive in one of the world's largest markets, and closes with an open call for founders building in this space.
Replit's CEO On The Only Two Jobs Left In The Company Of The Future
synopsis

Amjad Masad, Replit's CEO and co-founder, argues the company of the future will boil down to two roles — builders and salespeople — because AI agents are absorbing everything else, and he positions Replit itself as the platform racing to let non-technical "AI-native developers" build real, scalable businesses through natural language and, soon, high-level goals rather than prompts.

Origin and the shift away from developers. Masad traces his frustration to watching developer tooling get harder across his career, from BASIC to a painful React/Webpack setup, driving Replit's original mission of making programming accessible. As the product matured, he noticed the people getting the most value weren't trained engineers but product managers, designers and entrepreneurs, so in 2023 Replit explicitly stopped building for traditional developers. He points to a physical therapist who built a sophisticated body-tracking app after being frustrated by outsourced developers, and founders building software for pool businesses and sports clubs still running on MS-DOS.

Enterprise traction and sales motion. Inside companies, Masad describes two use cases: product teams shipping faster (he cites Whoop going from trying roughly 5 of every 100 ideas to about 50) and operations staff building internal tools to cut SaaS sprawl. Distribution blends product-led growth with a "sales-as-evangelism" motion — hackathons and executive education building internal champions — alongside traditional enterprise sales built on Replit's security and compliance record.

Agent 4's bets. Masad says Replit times a new agent to each roughly six-month jump in frontier AI capability. Agent 3 targeted multi-hour autonomy; Agent 4 adds parallel agents, an asynchronous design canvas, and multiplayer sessions where each collaborator forks their own VM.

YC's imprint. He credits YC's three-month sprint mentality and 7%-weekly-growth heuristic as still-used internal tools, and credits a YC-brokered introduction to Marc Andreessen with landing Replit's seed round after early fundraising failed.

The forecast. Masad expects a "post-prompting" era where agents take high-level goals, constrained mainly by weak computer-use models and the absence of true continual learning — with the future firm made of generalist builders directing agents and salespeople surviving as trusted human educators.

  • Replit deliberately targets tech-adjacent creators, not classic developers. Amjad Masad, Replit's CEO, says the users getting the most value are product managers, designers and entrepreneurs who don't want to touch environment setup or deployment, and in 2023 the company made it an explicit goal to stop building for traditional developers in favor of what he calls "AI-native developers."
  • Enterprise clients are reporting an order-of-magnitude jump in idea throughput. Masad cites Whoop as an example, saying the company used to generate around 100 product ideas but could only afford to try five of them, and can now try roughly 50 because product and design staff, not just engineers, can build working software themselves.
  • Agent 4's redesign targets the "boredom" of watching an agent work. Masad says the release adds parallel agents, an asynchronous design canvas so users can keep working while code builds in the background, and multiplayer sessions where each collaborator forks their own virtual machine, all aimed at autonomy running for hours at a stretch.
  • He predicts a "post-prompting" future built on just builders and salespeople. Masad expects agents will soon take high-level goals rather than detailed prompts, with salespeople surviving as evangelists and educators because customers still trust humans, and builders becoming generalists who direct agents — citing an internal Replit team that improved support-ticket prioritization and built an HR onboarding tool without a defined mandate.
How To Build A Company With AI From The Ground Up
  • AI-native companies should run as "closed loops," not open ones. Diana, a YC partner, argues every process should feed its outcomes back into an AI layer with full context — meetings, dashboards, Slack, tickets — rather than relying on manual status updates; she cites YC companies giving an agent access to Linear, Slack and customer feedback to generate sprint plans, cutting sprint time in half and getting close to 10x more done.
  • "AI software factories" replace code with specs and tests agents iterate against. Diana describes this as the next evolution of test-driven development, where humans define success criteria and judge output while agents write and iterate on the implementation, pointing to StrongDM's engineering team as having pushed this far enough that their repos contain no hand-written code.
  • Management hierarchy stops making sense in a fully AI-legible company. Diana relays Jack Dorsey's view at Block that companies must be rebuilt around an intelligence layer rather than human routing, replacing traditional management with three roles: the individual contributor who builds, the directly responsible individual accountable for one outcome, and a founder who leads by using the tools directly.
  • Startups have a structural edge over incumbents in going AI-native. Diana argues early-stage founders can design workflows and culture around AI from day one, unlike established companies that must unwind existing systems and processes — citing Mutiny's use of a separate internal skunkworks team as one way larger companies try to work around that constraint.
How to Make Claude Code Your AI Engineering Team
  • The bottleneck in AI coding is thin scaffolding, not model intelligence. Garry Tan, YC's president and CEO, argues Claude Code's models are already capable enough that guessing at an unfamiliar codebase — not weak reasoning — produces plausible-looking code that silently breaks, which is why he built G-Stack around a "thin harness, fat skills" approach that has passed 70,000 GitHub stars.
  • The "Office Hours" skill reframes an idea the way YC partners do. Demoing a tax-document app idea, Tan shows it asking for evidence anyone wants the product, questioning why TurboTax or Plaid don't already solve it, and reframing a simple document aggregator into a wedge toward a CPA-marketplace lead-gen business.
  • Adversarial review automatically caught and fixed most gaps in a design doc. Tan says the design document survived two rounds of multi-step adversarial review that caught 16 issues, most auto-fixed, raising its self-assessed score from 6/10 to 8/10 before he approved it.
  • Tan runs parallel Claude Code sessions and ships dozens of PRs daily. He says he runs 10 to 15 sessions at once and ships up to 50 PRs in a day, after building a custom CLI wrapper around Playwright and Chromium for browser-based QA when the Claude-in-Chrome MCP tool proved too slow and unreliable — a setup he describes as reaching "level seven" of an eight-level software factory.
How Stripe Built Their New Website
synopsis

Katie Dill, Stripe's head of design, walks through the year-plus redesign of Stripe's homepage and lands on a consistent position: AI tools have made design exploration dramatically faster, but the final quality of the new site came from human craft, iteration and a deliberate refusal to settle for "good enough" — not from the tools themselves.

Why the old site had to go. Dill says the 2020 homepage still looked visually current after six years, so the redesign wasn't driven by the design aging out. Instead, Stripe's product suite had outgrown the story the site told — the company had expanded from payments into billing, tax, revenue recognition, usage-based AI billing and stablecoins, a shift Dill ties to the fact that over 78% of the Forbes AI 50 now use Stripe — leaving the old page an accumulation of bolted-on sections rather than a coherent narrative.

Building trust and scale into the page itself. Dill frames a website as a company's implicit manifesto and describes deliberately choosing signals only Stripe could credibly make, notably a live counter of the share of global GDP that runs through Stripe, alongside scrolling customer logos, to reassure both micro-entrepreneurs and large enterprises of its reliability.

Iterating toward the Bento layout. The team tested several ways to convey Stripe's now-sprawling product line, including a dense single-screen layout and a tap-to-expand accordion; user research showed people don't click tabs, killing the accordion for a visual "Bento" grid with pop-up modals that shows products through imagery and keeps visitors on the page. A custom internal tool let the team tune the homepage's gradient-wave visuals — blur, grain, color, rotation — across dozens of variants before Patrick Collison and the team converged on a direction, pushing the launch past December because a set of card animations didn't yet feel smooth enough.

AI's role, and where it stops. Dill says AI sped up image generation and prototyping enough that the team could review roughly 20 directions in the time two used to take, and expects AI-managed design systems to help teams scale a coherent visual language faster. But she stresses AI raises the floor to a "seven out of ten" baseline without replacing taste, attention to nuance (an AI-generated hand or shadow that looked almost right), or craft — warning designers not to be "wooed" into accepting AI output as finished. She closes on Stripe's culture of fighting "the gravitational pull to mediocrity," prototyping from the user's actual experience rather than presenting rationale to stakeholders, and "walking the store" — weekly sessions, including ones led by Stripe's founders, where staff use Stripe's own products to catch dead ends and inconsistencies across its business lines.

  • Stripe's product suite outgrew its old site's story. Katie Dill, Stripe's head of design, says the 2020 homepage still looked current but no longer conveyed a business that had expanded from payments into billing, tax, revenue recognition, usage-based AI billing and stablecoins — not the design aging poorly — a shift she notes drives use by over 78% of the Forbes AI 50.
  • A live GDP counter was a deliberate, hard-to-copy trust signal. Dill says the team added a live counter showing the share of global GDP that runs through Stripe to demonstrate reliability at scale to customers ranging from micro-entrepreneurs to large enterprises, choosing that specific metric because few other companies could credibly claim a comparable figure.
  • User research killed an accordion-style layout because people simply don't click tabs. Dill says testing showed the tap-to-expand format required too much effort for visitors in "browse mode," which pushed the team toward the more visual "Bento" grid with pop-up modals that shows products directly rather than requiring interaction to reveal them.
  • AI sped up prototyping but didn't replace design judgment. Dill says the team could review roughly 20 visual directions in the time it used to take to review two, using a custom internal tool to tune the homepage's gradient-wave visuals, but still chose to push the launch past December because a set of card animations didn't yet feel smooth enough.
The GPT Moment for Robotics Is Here
synopsis

Qiong (Quan) Wang, co-founder of Physical Intelligence, ends up arguing that robotics has quietly crossed a threshold: general-purpose models, mixed human-robot operation, and collapsing hardware costs now make it possible for a small, scrappy team to deploy a profitable robot in a real workflow without building the fully vertically integrated stack robotics companies used to need — and he predicts this will trigger a "Cambrian explosion" of vertical robotics startups.

Why robotics was hard, and what cracked it. Wang frames the problem as three pillars — semantics, planning and real-time control — and traces how language models solved the first two: SayCan showed language models could plan steps for a robot, and PaLM-E and RT-2 showed a vision-language model could translate that plan into low-level robot actions, transferring knowledge (like recognizing Taylor Swift in a photo) the robot had never seen in its training data. The remaining bottleneck was scaling across incompatible hardware, which Physical Intelligence's Open X Embodiment project addressed by training one generalist policy on data from 10 robot platforms — outperforming ten single-platform specialists by 50%, a result Wang calls surprising given how brittle single-robot training usually is.

What's working today. Wang says the field has reached the point where, for tasks where occasional robot mistakes are tolerable, a "mixed autonomy" system — a human stepping in to correct errors — can already justify scaling deployment. He walks through two YC-company collaborations: Weave's robot folding varied, previously-unseen laundry in a real laundromat, and Ultra's system packing e-commerce orders into shipping pouches across a full day inside a live warehouse with only minimal human intervention — both real commercial operations, not lab demos.

The technical unlock: cloud-hosted control. Contrary to robotics orthodoxy that control must run on-device, Wang says nearly all of Physical Intelligence's robots query a model hosted in an actual cloud data center within the real-time control loop. This works because of "real-time chunking," an inference technique that precomputes overlapping sequences of actions so the robot always has something to execute while the next chunk is still being predicted, hiding network latency and removing the need for expensive onboard compute.

The new playbook, and the forecast. Wang lays out a recipe for founders: deeply understand an existing workflow, identify where a robot creates the most value, use cheap and imprecise hardware since reactive models can compensate, and get to break-even mixed-autonomy operation before scaling robot count — arguing this last step, historically the hardest, is what actually determines whether a robotics company can grow. He backs this with rough math that fully solving robotics could add on the order of 10% to U.S. GDP. To accelerate the resulting startup wave, Physical Intelligence open-sourced its Pi Zero and Pi 0.5 model weights identical to its internal versions, and Wang closes by naming gaps he sees as remaining opportunities: robotics still lacks shared infrastructure for data collection, annotation and evaluation that other companies could build as a service.

  • One model trained across many robot bodies beat single-robot specialists. Qiong (Quan) Wang, co-founder of Physical Intelligence, says their Open X Embodiment experiment trained a generalist policy on data from 10 different robot platforms and found it performed 50% better than ten specialist policies each optimized for a single platform.
  • Physical Intelligence's robots run on a model hosted in the cloud. Wang says nearly all their demos, including laundry folding and mobile navigation, query a real cloud data center over an API within the control loop, made workable by an algorithmic technique he calls "real-time chunking" that precomputes overlapping action sequences so network latency doesn't stall the robot.
  • Two YC-backed deployments show the mixed-autonomy approach already running real commercial work. Wang describes Weave's robot folding varied, unseen laundry items in a real laundromat, and Ultra's system packing e-commerce orders into shipping pouches inside a live warehouse for a full day with only minimal human intervention — not lab demos, but real customer orders being fulfilled.
  • Wang predicts a "Cambrian explosion" of vertical robotics startups. He argues cheaper hardware, models reactive enough to compensate for imprecise motion, and a path to break-even economics via mixed human-robot operation let a small, scrappy team build a vertical robotics company without the full vertical integration the field used to require — and Physical Intelligence open-sourced its Pi Zero and Pi 0.5 model weights, identical to the versions used internally, to accelerate it.
BillionToOne Is Solving One of Biotech’s Hardest Problems
  • A synthetic-DNA spike-in turns a biology problem into a math problem. Co-founders Ozan and David say BillionToOne adds known synthetic DNA to a blood sample before PCR amplification, which lets them measure exactly how much distortion and error the amplification process introduces at each genomic location and mathematically subtract it — the technique behind a prenatal test now processing over 600,000 tests a year and holding roughly 20% market share.
  • An emergency sales push, not a science fix, saved a stalled launch. Two months after launching, only one physician was ordering the test; David describes hiring and training five additional sales reps within three weeks and having reps spend 30-45 minutes per patient explaining the test so patients would push their doctors, which lifted kit return rates to about one in five and gave them the traction needed to hire experienced sales staff.
  • BillionToOne deliberately sequenced its roadmap from cheapest to most capital-intensive market. The founders say they mapped out prenatal testing, then late-stage cancer, then early-stage cancer detection as early as 2018, funding each harder, more expensive step with revenue from the last rather than raising over a billion dollars upfront for early cancer detection — the approach they credit with letting first-time, resource-constrained founders reach a "holy grail" problem others couldn't afford to attempt.
  • The company staffs itself with "interdisciplinary people," not interdisciplinary teams. Ozan says small pods of one principal-investigator-level scientist plus two or three research associates own a product end-to-end and report directly to the co-founders, which he says removes bureaucratic bottlenecks and speeds iteration by an order of magnitude compared to splitting chemistry and data-analysis expertise across separate specialists.
This Startup Catches Fraud at Scale
synopsis

Karim, co-founder of Variant, frames the company's exit from three years of stealth and its $21 million Series A as proof AI agents have finally closed a loop fraud teams could never close with rules engines, classifiers and human reviewers — with Variant, though largely invisible publicly, now underpinning compliance decisions at GoFundMe, IAC brands and other large platforms.

Origin and first customer. Karim and co-founder Michael met running Apple's internal fraud-engineering team and built Variant around one fixed thesis. Landing their first enterprise customer, IAC, took eight months; Karim credits founders who'd visibly lived the problem and a compliance pain acute enough — reviewing marketing content by hand at BPO scale — to trust an unproven startup, just as GPT-4's mid-pilot release reshaped their costs and performance.

The technical shift. Karim contrasts old fraud stacks — rigid rules, narrow classifiers, slow human judgment — with agents that read a company's compliance documents and reason directly over unstructured data, including scraping legacy dashboards via a spun-up browser when no API exists. He cites detecting state-sponsored election fraud rings and credible physical-threat cases, both requiring reasoning across a full entity graph that isolated classifiers couldn't do, with findings passed to law enforcement.

Scaling small. Variant runs on 12 people, five engineers, each managing multiple parallel coding agents for roughly a 25-person team's output — including a non-technical customer success manager who ships simple feature requests herself through a coding agent.

The interruption. Growth was compounding — revenue doubling month over month by mid-2024 — when Karim, the company's only salesperson, was hit by a truck and hospitalized for 10 days with a broken spine and leg, leaving Michael to wonder if the company could survive before Karim recovered.

  • AI agents replaced three separate legacy fraud-detection systems with one self-healing loop. Karim, Variant's co-founder, says companies used to stitch together rules engines, narrow classifiers and slow human reviewers, but agents can now read a company's own standard operating procedures and reason directly over unstructured data — and when a customer has no API, Variant's agents scrape data by operating the same legacy review dashboard a human analyst would have used.
  • Reasoning across a full entity graph caught fraud isolated classifiers missed. Karim describes detecting coordinated, state-sponsored fraud rings pushing a single narrative during an election cycle, and separately catching people making credible, at-scale threats of physical violence, by having agents relate each account to every other account rather than scoring one piece of content in isolation — cases that were then referred to law enforcement.
  • Coding agents let five engineers ship roughly a 25-person team's output. Karim says every engineer runs multiple AI coding agents in parallel while still reviewing all pull requests, and gives an example of a non-technical customer success manager taking a customer's feature request straight to a Cursor agent and shipping it without ever looping in engineering.
  • The company nearly ended when a truck hit its only salesperson. Karim, who ran all of Variant's sales himself, describes revenue doubling month over month through mid-2024, then breaking his spine and leg in a cycling accident that hospitalized him for 10 days, leaving co-founder Michael, on an engineering-only team, questioning whether the company could continue.
" It is very possible that the first people to live to a thousand are alive right now."
  • The first people to live to 1,000 may already be alive today. The speaker argues AI's disruptive potential remains underpriced by the public and that brain-computer interfaces — a separate but parallel development — will reframe the human condition by around 2035, though he stops short of predicting all disease will be cured by then.
François Chollet: Why Scaling Alone Isn’t Enough for AGI
synopsis

François Chollet, creator of the ARC-AGI benchmark and founder of the research lab Indium, ends up arguing that scaling the current deep-learning stack will keep making AI more useful without making it more intelligent, that his own symbolic alternative has only a 10-15% chance of working but is worth pursuing precisely because almost no one else is trying it, and that true general intelligence — by his own definition — is still roughly a decade away, around the early 2030s.

From believing deep learning could do everything to designing ARC. Chollet, creator of Keras, recounts believing around 2015 that deep learning was effectively "differentiable programming," capable of learning any algorithm given the right data. Research at Google Brain on automating logical reasoning changed his mind: models could represent reasoning algorithms, but gradient descent could not find them, instead producing overfit pattern-matching. That gap led him to design the ARC benchmark, published in 2019, around a specific definition of intelligence as skill-acquisition efficiency rather than task performance — a benchmark largely ignored until reasoning models arrived.

What ARC's history actually shows. Chollet says ARC-1 stayed nearly unsolved through a 50,000x scale-up in pretrained model size, and only jumped when OpenAI's o1 and o3 reasoning models arrived in late 2024. ARC-2 was later saturated, but Chollet attributes this to labs building custom harnesses that generate synthetic tasks, verify solutions, and fine-tune on the successful reasoning chains at massive scale — a process he says reflects better training and tooling, not higher fluid intelligence, and describes as a fundamental trade-off where more knowledge lowers the intelligence needed for competence.

ARC-AGI-3 and agentic intelligence. To measure something harder to game, Chollet's team — including a hired video-game studio — built over 250 environments that give an agent no instructions, no stated goal, and no cultural symbols to lean on, scoring it on matching human-level efficiency at exploring, forming a world model, and achieving goals through trial and error. Unlike training-and-testing on the same environment (as in older systems like OpenAI Five or DeepMind's Atari work), ARC-3 agents face games they've never seen, with a private test set deliberately built around different concepts than the public one to resist the same large-scale harness-targeting that cracked ARC-2.

Indium's bet: symbolic descent. Chollet describes his lab's core wager as replacing parametric curves and gradient descent with the shortest possible symbolic model that explains the data, found via deep-learning-guided search over a combinatorial space — a method he compares to AlphaZero. He predicts that a true "fluid intelligence engine," once built, will retrospectively look like fewer than 10,000 lines of code sitting atop a much larger, separately scalable knowledge base, and that human cognition performs something like program synthesis even though the human brain itself is too messy a target to copy directly.

Advice, not fear. Chollet closes by rejecting pessimism about AI-driven unemployment, arguing deeper domain expertise makes AI more useful to a person, not less relevant — recommending that people, especially those early in their careers, build real skills specifically so they can leverage accelerating AI progress rather than be displaced by it.

  • Chollet's new lab wants to replace deep learning with tiny symbolic models. François Chollet says his lab, Indium, is pursuing "symbolic descent" — searching for the smallest symbolic program that explains a dataset instead of fitting parameters via gradient descent — betting this yields models needing far less data and generalizing better, though he puts the odds of the approach succeeding at only 10-15%.
  • Chollet expects task automation to arrive well before true general intelligence. He separates the industry's usual definition of AGI (automating economically valuable work) from his own (matching human data-efficiency at learning any new task), and argues today's LLM-based systems can already fully automate any domain with a verifiable reward signal — starting with code and, he predicts, mathematics next — while unverifiable domains like essay-writing will progress much more slowly.
  • ARC-AGI's benchmark history shows models getting more useful without getting smarter. Chollet says reasoning models produced a step-function jump on ARC-1 in late 2024, while ARC-2 was later saturated not by higher fluid intelligence but by labs building custom harnesses that generate, verify and fine-tune on millions of synthetic reasoning chains — evidence, he argues, that recent gains reflect better training and tooling rather than a rise in raw intelligence, though he notes one YC company reached 97% on ARC-2 with this approach.
  • ARC-AGI-3 tests whether an AI learns new games as efficiently as humans. Built with a hired game-development studio, it drops agents into more than 250 unlabeled environments where every exploratory action counts against an efficiency score benchmarked against human testers, and deliberately keeps its private test set conceptually different from the public one to resist the same harness-driven gaming that saturated ARC-2; Chollet predicts AGI around the early 2030s, roughly when his team releases ARC-6 or ARC-7.
Differences Between The Leading AI Models
  • Frontier models already show distinct strengths, but will commoditize within years. The speaker says Opus is a strong all-around workhorse, Codex excels at backend debugging and Gemini at frontend work, letting their product lean on each model's "spike"; they expect open source to trail by roughly three to six months and all models to converge on similar capability and pricing, leaving the advantage to whoever best serves the user.
Inside The Startup Reinventing The $6 Trillion Chemical Manufacturing Industry
  • A pancreatic-cancer enzyme became the key to a new manufacturing process. Co-founder Gora, then in medical school studying pancreatic cancer, found tumor cells locally generating roughly 50% hydrogen peroxide concentrations via a mutated enzyme; pairing that enzyme with a metal catalyst — a combination Solugen calls chemoenzymatic processing — pushed reaction yield from a typical 60% to 96% at scale.
  • Solugen deliberately avoided the large-plant-first approach that had sunk earlier bio-chemical startups. Co-founder Sean says they built their first reactor for $10,000 out of PVC pipes from Home Depot and started selling small volumes of peroxide to hot tub owners in Dallas almost immediately, arguing capital constraints forced creative thinking and that deep, direct customer knowledge — not a big plant — determined what they could actually build.
  • A hyper-targeted, unconventional sales tactic landed Solugen's first oil-and-gas field trial. Sean describes identifying the one person at a saltwater disposal company who controlled chemical purchasing, then buying billboards along his commute route for roughly $10,000-$15,000 so he would recognize the company by the time they called him.
  • Solugen's flagship plant is its original prototype, scaled roughly 1,400x. Sean says the 60-foot bubble-column reactor at their Bioforge 1 facility is functionally identical to their original Y Combinator-era PVC reactor, just 10,000 gallons instead of 7, and that one bottle-sized dose of enzyme yields two to four tanker trucks of finished product; the company builds smaller plants near customers rather than one mega-facility to undercut larger competitors on shipping costs.
This Is The Holy Grail Of AI
  • Puddle's founder claims the startup can do recursive self-improvement far cheaper than approaches that require retraining a new model from scratch. He says the standard approach costs hundreds of millions of dollars and months of effort per model; pressed that incumbents could still out-release them, he responds that Anthropic, OpenAI and Google are pursuing self-improvement too, but typically still at the expensive full-retrain-per-step level.
AI Is Unlocking Millions Of New Builders
synopsis

Twin brothers Mukund and Madhav Jha, founders of Emergent, end up arguing that AI coding agents are triggering a "Cambrian explosion" of solo, non-technical founders building real businesses — not the mass knowledge-work displacement the industry usually discusses — because Emergent treated shipping production-ready software, not front-end prototyping, as the problem to solve from day one.

Two pivots to find the market. Mukund says Emergent began in late 2023 automating software testing, a bottleneck he'd seen running a 300-engineer team at Dunzo. Building test agents revealed that solving verification is what lets an agent run autonomously for long stretches, so the brothers pivoted to a general coding agent, reaching #1 on the SWE-bench benchmark within two months by inventing multi-agent orchestration and cross-session memory before those ideas appeared in published research. An initial enterprise push proved too slow, and watching Lovable and Bolt grow pushed them toward non-technical consumer builders instead — a bet that now accounts for 80% of users across 7 million apps built in 8 months, spanning over 190 countries.

Building for the "last mile." Where competitors optimized for quick prototypes, Emergent built its own Kubernetes-based cloud sandbox infrastructure so the environment an app is built in matches the one it deploys to, reducing deployment failures. Its multi-agent system delegates tasks like testing or API integration to sub-agents, and accumulates a long-term memory of "skills" distilled from past sessions — a process Mukund says must run through a separate pipeline rather than being self-generated, since agent-authored skills underperform. The team also deliberately hides technical affordances like raw diffs from non-technical users who found them intimidating.

Dogfooding and a lean team. Emergent's own project-management tool, an agent-built Asana/Jira clone that started as a QA engineer's "clone Jira" prompt, now runs the whole company with no hand-written code, saving roughly $3,000-$4,000 a month. Every employee, including non-engineers, takes customer-support shifts, a practice Mukund credits with building the customer empathy that shaped the product. Hiring indexes heavily on raw problem-solving and ownership — pulling from top-ranked Indian engineering programs and prior Dunzo colleagues — letting a handful of people own entire systems, like a two-person deployment stack and a one-person memory system.

What this unlocks. Mukund closes on stories he sees as evidence of the platform's real impact: a clinical psychologist and equestrian coach in Alaska who built a niche app combining both fields after a dev shop's quote proved unaffordable, custom software dropping from roughly $500,000 to about $5,000 to build, and one Emergent-built app reportedly raising $4 million. He argues this expands the market rather than shrinking it, predicting existing SaaS tools will either become agent-first or lose users to people building their own customized software instead.

  • Emergent pivoted twice before finding its market, chasing verification, then non-technical builders. Co-founder Mukund Jha says the company started in late 2023 automating software testing, then realized solving verification lets a coding agent run autonomously for much longer, which led them to build a general coding agent that hit #1 on the SWE-bench benchmark within two months — before they abandoned an enterprise push and repositioned for non-technical users, who now make up 80% of the platform's builders across 7 million apps built in 8 months.
  • Emergent built its own cloud infrastructure so build and deploy environments match. Jha says they run their own Kubernetes-based sandbox stack rather than a third-party provider specifically to avoid deployment failures, pairs a multi-agent architecture that delegates tasks like testing or API integration to sub-agents, and gives agents a long-term memory built from auto-generated "skills" distilled from past session trajectories — which he says must be generated by a separate CI/CD-style process rather than by the agent itself to actually improve performance.
  • Emergent dogfoods its own product, including an agent-built Asana clone. Jha says a QA engineer's side project of prompting "clone Jira" grew into a project-management tool now used company-wide, built entirely on Emergent with no hand-edited code, saving roughly $3,000-$4,000 a month in subscription costs, and that every employee — including non-engineers — does customer support shifts to stay close to user needs.
  • Non-technical domain experts are shipping real, previously-impossible businesses. Jha cites a clinical psychologist and equestrian coach in Alaska who built "EquiMind," an app combining both fields, after a Nova Scotia dev shop quoted her a price she couldn't afford; he frames custom software that used to cost around $500,000 as now buildable for roughly $5,000, and mentions one app built on Emergent has reportedly raised $4 million in funding.
Startup School is coming to India! 🇮🇳
  • YC is bringing Startup School to Bangalore for the first time, on April 18. The one-day event gathers top Indian builders and hackers and features founders of YC-backed Indian companies including Razorpay, Meesho, Groww and Emergent.
The Future Of Brain-Computer Interfaces
synopsis

Max Hodak, co-founder of Neuralink and founder of Science, argues brain-computer interfaces are a distinct, longevity-and-consciousness story rather than an AI one — that we've entered a "takeoff era" akin to the industrial revolution's earliest years, that people alive today may live to 1,000, and that he can't forecast the field past an "event horizon" around 2035.

What Science has actually proven. Hodak frames Science's Prima retinal implant as evidence the field has moved past incrementalism: a clinical trial published in the New England Journal of Medicine, spanning more than 40 patients across 17 European sites, let people who'd been unable to see faces for a decade read letters on an eye chart. He credits this to a specific technical choice — stimulating the retina's bipolar cells, one processing layer upstream of the optic nerve, rather than the ganglion cells a earlier device called Second Sight had targeted directly. Because the ganglion layer had already compressed the visual signal, stimulating it produced only meaningless flashes patients' brains could never assemble into images; stimulating bipolar cells instead preserved that critical processing step and produced what Hodak calls the first true "form vision" from a brain prosthesis.

How they got there. Hodak contrasts a slow, unreliable "drug discovery" model of medicine with the "neural engineering" approach behind Science: since the company wasn't founded around one patented asset, it systematically explored a 2-by-2 matrix of stimulation options — bipolar versus ganglion cells, electrical versus optogenetic — before settling on electrical stimulation of bipolar cells, acquiring a Stanford-derived technology a small European company had been developing. An in-house optogenetic alternative, sensitive enough to activate under ordinary indoor lighting, remains 5 to 7 years from clinical use.

The limits and surprises of plasticity. Hodak describes the brain as more plastic in adulthood than widely appreciated, citing early motor-decoding experiments where a handful of neurons were arbitrarily and permanently mapped to cursor movement, and patients' brains learned to control the mapping anyway. But this plasticity has hard edges: adults born blind from congenital cataracts and later surgically given sight could never learn to interpret the input past a missed critical developmental window, and some of those patients died by suicide.

The next frontier: biohybrid interfaces. Beyond Prima, Hodak describes Science's most speculative project — a "biohybrid" interface that grafts living, engineered, immune-evading stem-cell-derived neurons onto the brain, letting them biologically grow their own connections rather than requiring inserted wires or gene therapy that edits the patient's own neurons. He traces the intuition to the brain's corpus callosum and to a pair of conjoined twins in Canada who, connected by a single neural cable between their thalami, appear to share elements of conscious experience directly — a case study he treats as evidence that a sufficiently high-bandwidth connection could functionally create a new sense, effectively a new cranial nerve.

Origin and closing philosophy. Hodak traces his path from an undergraduate neuroscience lab at Duke through founding a robotic cloud-lab startup, to receiving Sam Altman's 2016 email asking who should run "Elon's brain computer interface company," which became Neuralink. His advice to early-career builders: combine high agency with an early stint working for an accomplished mentor rather than going it alone. He closes by distinguishing BCI's endpoint from AI's: where AI's trajectory points toward superintelligent machines, he argues BCI's points toward understanding — and eventually building — conscious ones, calling this "a very different narrative than how people usually think about BCI today."

  • Science's retinal implant produced the first-ever coherent "form vision" from a prosthesis. Max Hodak, the company's founder, says their clinical trial — published in the New England Journal of Medicine, covering more than 40 patients across 17 European sites — let people who'd been unable to see faces for a decade read letters on an eye chart, which he attributes to stimulating the retina's bipolar cells rather than the optic nerve's ganglion cells, preserving compression the retina had already done; an earlier device from a company called Second Sight, which stimulated ganglion cells directly, produced only meaningless flashes that patients' brains never assembled into images.
  • Adult brains stay far more plastic under feedback than commonly believed. Hodak says early motor-decoding experiments deliberately used fixed, arbitrary mappings between a few neurons and cursor movement, and patients' brains learned to control the mapping regardless — evidence, he argues, that plasticity persists throughout adulthood — but contrasts this with adults born blind from congenital cataracts whose sight was surgically restored decades later and whose brains, past a critical developmental window, could never learn to interpret the input, with some patients dying by suicide.
  • Science tested every stimulation approach before choosing electrical bipolar-cell stimulation. Hodak describes exploring a 2-by-2 matrix of choices — stimulating bipolar cells versus optic nerve ganglion cells, done electrically versus via optogenetics — and rejecting ganglion-cell stimulation because it required an impractical million-degree-of-freedom calibration per patient; the company still develops an in-house optogenetic alternative sensitive enough to activate under ordinary indoor lighting, which Hodak estimates is 5 to 7 years from clinical use.
  • Science's "biohybrid" interface grafts living neurons onto the brain itself. Hodak says the approach — inspired by the brain's own corpus callosum and by conjoined twins in Canada who share elements of conscious experience through one connecting nerve bundle — seeds a device with hypoimmunogenic, stem-cell-derived neurons that biologically wire into the patient's brain without inserting wires or genetically modifying the patient's own cells, avoiding the largely irreversible risk he says comes with gene-therapy-based approaches like optogenetics.
Common Mistakes With Vibe Coded Websites
synopsis

AI coding tools have made a professional-looking landing page nearly free to produce, but Garry Tan and YC visiting partner Raphael Schaad's review of six YC company sites arrives at a warning: the same training data that lets a good idea spread instantly also flattens every startup's site into the same purple-gradient, fade-in, scroll-jacked template, and only a founder who stays the deliberate "editor" of the AI's output — rather than accepting whatever it generates — ends up with something distinctive.

Why everything suddenly looks the same. Schaad traces the pattern to how it started: he noticed a wave of "dumb hover effects" on startup landing pages and realized that once one well-linked site established a trend, it entered LLM training data and propagated to every other AI-built site within a week, instead of the months such copying took in the pre-LLM era. The clearest symptoms across the reviewed sites — new.ai/Nunu, Rosebud AI, Get Crocs, Sphinx, Build Zero, Zarna — are near-identical purple gradients, sections that fade in and out on scroll, and animated lines that trail the cursor down the page.

Motion and hover used against the user. Several sites use hover to make menu items and buttons fade or disappear rather than "pop," which Schaad calls an anti-pattern since browsers already signal clickability with the cursor and hover has no mobile equivalent. Get Crocs's call-to-action button chases the cursor around the screen, and Zarna's scroll-jacked page — plus Sphinx's auto-advancing, reshaping buttons — leave reviewers unable to tell what's clickable or how far into the page they are, pulling attention away from the actual value proposition.

What actually works. Not every AI-enabled effect fails: Nunu's hover-triggered card animations are called "tasteful," reinforcing the brand with imagery too costly for a human to have hand-coded, and Sphinx's headline is praised for clearly stating what the product is, who it's for, and why they should care — the three things Schaad says must sit above the fold.

The fix. Tan and Schaad's shared advice: QA everything by hand, since one-shotted pages ship undetected bugs (a broken selection state on Build Zero, semi-clickable elements on Zarna) that a hand-built site wouldn't; and start from your own brand and color palette rather than the AI's defaults, using the time AI saves to sharpen messaging and product instead.

  • LLM-trained design clichés are homogenizing startup websites overnight. Raphael Schaad, YC visiting partner, argues purple gradients, cursor-trailing lines, and scroll-triggered fade-ins spread instantly once one well-linked site enters LLM training data — a process that used to take months of manual copying before AI design tools existed.
  • Hover effects on AI-built sites frequently hide rather than reveal. Menus and buttons on sites like Nunu (new.ai) fade or vanish on hover instead of "popping," which Schaad calls an anti-pattern since browsers already signal clickability and hover has no mobile equivalent, making it a poor place to hide essential functionality.
  • Scroll-jacking and cursor-chasing buttons distract more than they convert. Garry Tan and Schaad found Get Crocs's roaming call-to-action button and Zarna's hijacked, molasses-slow scroll pulled their attention away from the actual value proposition rather than toward it.
  • Founders must edit AI output, not accept it as final. Schaad points to undetected bugs shipped on one-shotted pages — a broken selection state on Build Zero, semi-clickable elements on Zarna — and advises starting from a company's own brand and color palette rather than whatever the AI defaults to.
Startup School 2026
  • YC's Startup School returns for two days in San Francisco, July 25–26, with speakers including Jensen Huang, Sam Altman, Alexander Wang and Jeff Dean. The event targets top undergrads, grad students and researchers in CS, ML, applied math and engineering, offering direct access to YC partners and alumni; YC says over 100 attendees from last year's event are now YC founders.
The Powerful Alternative To Fine-Tuning
  • Poetic builds AI harnesses, not fine-tuned models, atop frontier LLMs. Ian Fisher, co-founder and co-CEO, argues fine-tuning becomes worthless once a new frontier model ships, since firms have sunk hundreds of millions into a now-obsolete base; his "meta system" instead auto-generates reasoning harnesses that stay compatible and keep improving for free as underlying models advance.
  • A harness beat Google's top model on ARC-AGI for less money. Fisher says that two days after Gemini 3 Deep Think posted 45% on ARC-AGI v2 at roughly $70 per problem, Poetic's system — built on the cheaper Gemini 3 Pro — reached 54% at $32 per problem.
  • Poetic also edged Anthropic's Opus 4.6 on Humanity's Last Exam. Fisher reports Poetic scored 55% on the 2,500-question expert benchmark, versus Opus 4.6's 53.1% announced the previous week, at an optimization cost he says was under $100,000, done by a seven-person team.
  • Automated reasoning strategies, not better prompts, drive the biggest gains. Fisher cites earlier DeepMind work where manually engineered reasoning strategies lifted Gemini 1.5 Flash's score on a hard task from 5% to 95%; Poetic's meta-system now discovers such strategies itself rather than relying on hand-tuned prompts or curated datasets.
Coding Will Be Solved For Everybody
  • The "software engineer" title will fade as coding becomes a universal skill rather than a separate job. The speaker says every function on their team already codes — PMs, designers, the engineering manager, even finance — and expects engineers' work to broaden into writing specs and talking to users as this pattern spreads industry-wide.
The AI Agent Economy Is Here
  • Agents now pick dev tools by parsing documentation, not word of mouth. YC partners argue this is reshaping dev-tool go-to-market, citing a surge in Postgres databases created over the past year as agents building apps default to Supabase, whose documentation they say is simply the best-written for an LLM to parse.
  • Resend rebuilt its docs to be agent-readable, and it worked. The email-sending company's founder noticed over a year ago that ChatGPT had become a top-three inbound channel, so he restructured docs into bullet-point Q&A with embedded code snippets; partners contrast this with SendGrid's support-ticket-gated docs, which they say leave it invisible to agents.
  • Documentation infrastructure is becoming a must-have, not a nice-to-have. Partners point to Netlify, built on better API documentation, as newly positioned to capture "exponentially more agents making exponentially more decisions" than developers ever did — meaning even a small documentation improvement could meaningfully move a dev-tool company's business.
  • Agent Mail's agent-only inboxes took off once OpenClaw exploded. The YC company built email accounts designed for AI agents because Gmail and other providers deliberately obstruct automated sign-ups to fight spam; partners speculate this points toward a fuller "agent economy" — even agent-native phone numbers — running alongside, and possibly eventually distinct from, human commerce.
What Boris Cherny Learned From Building Claude Code
  • Claude Code's creator didn't know at first that he had something, then became consumed building it. He describes working every night and weekend for three straight months without a vacation once he sensed "this is going to be a thing," even though it couldn't yet code; he says Anthropic's internal principle — build for the model six months out, not for today's — remains his advice to founders building on LLMs.
Inside Claude Code With Its Creator Boris Cherny
synopsis

Boris Cherny, Claude Code's creator, ends the conversation holding that coding is already "practically solved" for him personally — he hasn't written a line of code by hand since Opus 4.5 — and that this trajectory points toward software engineering dissolving into a more generalist "builder" role for everyone, even as the tool that got him there began as an accidental side project with no plan behind it at all.

An accident, not a plan. Cherny built Claude Code's first prototype just to learn Anthropic's own API: a terminal chat app, then an experiment with the newly released tool-use feature, ported from a Python doc example. Asking the model what music he was listening to and watching it write AppleScript to check was, he says, his first "AGI moment." Two days after he shared the prototype internally for dogfooding, a coworker was already using it to code; when Anthropic CEO Dario Amodei later asked why internal usage looked mandated, Cherny says there was no mandate — engineers had just started telling each other about it.

Building for a model that doesn't exist yet. Cherny's central design principle, learned at Anthropic, is to build for the model six months out rather than the one available today, since any scaffolding written to patch a current model's weakness typically gets its gains "wiped out" once the next model closes the gap for free. This is why the team kept Claude Code in a terminal rather than building a full IDE: no UI seemed likely to stay relevant for six months. A framed copy of Richard Sutton's "The Bitter Lesson" hangs in Cherny's work area as a reminder never to bet against the model.

Features built from user demand, not a roadmap. Cherny frames "latent demand" as the single biggest idea in product: don't invent new behavior, make an existing one easier. He says CLAUDE.md emerged from watching users write their own markdown instruction files, and "plan mode" was written in about 30 minutes on a Sunday night after he noticed GitHub issues and Slack feedback asking Claude to think without coding yet — it shipped the next morning. He now runs roughly 80% of his own sessions in plan mode, though he expects the feature has "a limited lifespan" as models need less explicit guidance.

Scaling results and how the team hires. Cherny cites internal figures showing per-engineer productivity, measured mainly by pull requests and cross-checked against commit data, up roughly 150% since Claude Code's release, and says Anthropic's code is now 70–90% Claude-written across teams, 100% for him personally. In hiring, he says he now favors "beginner mindset" and first-principles thinking over the strong opinions that used to mark senior engineers, since so much prior experience is now outdated; he screens for it by asking candidates to describe a time they were wrong.

The forecast, and its risk. Cherny's baseline prediction is that coding becomes "generally solved" for everyone and the title "software engineer" gives way to something more like "builder," with every function on a team — including PMs, designers, and finance — writing code, much as Anthropic's own team already does. The riskier upper bound is reaching what Anthropic calls ASL4, a recursively self-improving model, which carries release criteria the company says it is actively working to meet safely before any such threshold is crossed.

  • Claude Code began as an accidental internal prototype, not a plan. Boris Cherny, its creator, says he built a terminal chat wrapper just to learn Anthropic's API, added tool use experimentally, and only realized it mattered when a coworker used it to code the next day and CEO Dario Amodei asked why internal usage looked mandated — it wasn't.
  • Anthropic builds for the model six months out, not today's. Cherny says Claude Code is entirely rewritten every few months because scaffolding built to patch a model's weaknesses becomes wasted work once the next model closes the gap for free; his advice to founders is to build for the frontier the model hasn't reached yet.
  • Claude Code reportedly reshaped Anthropic's own engineering productivity. Cherny cites an internal measure — pull requests, cross-checked against commits — showing productivity per engineer up roughly 150% since the tool's release, with his own coding now 100% Claude Code and zero hand-written lines since Opus 4.5.
  • He predicts the title "software engineer" fades as coding gets solved. Cherny forecasts that as coding becomes "generally solved," roles will shift toward specs and user conversations across every function — he says Anthropic's PMs, designers, and even finance staff now code — while a riskier further frontier is ASL4-level recursive self-improvement, which he says Anthropic is actively working to make safe.
The New Way To Build A Startup
  • The leanest startups now automate every internal function, not just one. Garry Tan calls these "20X companies," extending Parker Conrad's "compound startup" idea from product breadth to internal operations — covering code, support, marketing, sales, hiring, and QA — which keeps payroll and headcount down as revenue scales.
  • One customer-service startup beat 20-times-larger rivals for a major account. GigaML's founders say they closed DoorDash as a customer with just four to five engineers against competitors with roughly 100x the headcount, crediting their internal agent Atlas — which can use browsers, edit policies, and write code — with doubling or tripling each engineer's scope.
  • One interface let a psychiatry network 4x patients with flat headcount. Legion Health built a single internal tool giving its care-ops team instant access to patient history, scheduling, and insurance codes; it says this let revenue and patient volume grow 4x in a year while staffing stayed at one clinical lead, one patient-support person, and one billing person.
  • A 12-person firm skips hiring by turning workflows into agents. Feathr, competing against accounts-receivable incumbents dating to 2006, has employees document their manual tasks so it can build custom agents for each; it says this let it avoid hiring a dedicated designer altogether, using an AI design tool instead for all front-end work.
Why OpenClaw Broke The Internet
  • OpenClaw's edge is running locally on a user's own computer rather than in the cloud. Speakers say that access lets it control anything connected to the machine — an oven, a Tesla, lights, a Sonos, even a smart bed — and describe it searching a user's files unprompted to compile a surprising narrative of their past year from forgotten old audio recordings.
AI Native Hedge Funds
  • AI-native hedge funds will emerge by inventing new strategies, the way quant funds did in the 1980s, not by bolting AI onto old ones. A former quant researcher recounts being ignored after asking compliance to approve ChatGPT use at a major fund, and argues the opportunity is swarms of AI agents combing 10-Ks, earnings calls and SEC filings to generate and trade on genuinely new strategies.
Stablecoin Financial Services
  • Stablecoins sit in a regulatory middle ground that opens room for new DeFi-meets-TradFi financial products. The speaker cites the GENIUS and CLARITY Acts as positioning stablecoins as compliant yet crypto-native, enabling services like yield-bearing accounts or tokenized real-world-asset access without forcing a choice between limited traditional products and unregulated crypto risk.
Large Spatial Models
  • Spatial reasoning, not just language, is the next frontier foundation-model category. The speaker argues current systems only handle basic depth and relationship tasks and can't robustly reason about 3D manipulation or mental rotation, and that a company treating geometry as a first-class primitive rather than a language add-on could become a foundation-model player on the scale of OpenAI or Anthropic.
AI for Government
  • Government needs AI tools to handle a coming surge of forms still processed by hand. The speaker points to Estonia as an early model of digital government and argues that, despite how hard it is to sell to government, landing a first customer tends to produce sticky contracts that expand over time.
Reindustrialize With Modern Metal Mills
  • Slow American mill lead times are ceding the metal market to cheaper, faster overseas competitors. The speaker says an aluminum plate can take up to 8 weeks and stainless steel for aerospace and defense up to 8 months from a US mill, and argues new domestic mill capacity is needed to support manufacturers like RMFG, Forge Automation and Atomic Industries.
OpenClaw Creator: Why 80% Of Apps Will Disappear
  • OpenClaw's edge is running locally with full control of your machine. Peter Steinberger, its creator, says cloud-only assistants are inherently limited while a local agent "can do every effing thing" — controlling smart devices, files, and any application the way a human user could.
  • A model improvised a voice-transcription pipeline it was never built for. Steinberger recounts sending OpenClaw a voice message while traveling with poor internet in Marrakech; with no transcription feature built, the model identified the audio format, converted it with FFmpeg, found a stored OpenAI key, and called the Whisper API via curl — replying in about nine seconds, which he says convinced him coding models' problem-solving generalizes to real-world tasks.
  • He predicts 80% of apps disappear as agents manage data directly. Steinberger argues most apps just manage data an agent could handle more naturally — tracking meals from a photo, adjusting a gym schedule, setting reminders — leaving mainly apps built around physical sensors, while large model companies keep a moat through memory and context locked inside their own data silos.
  • He skipped git worktrees and MCP support to cut complexity. Steinberger runs many parallel plain checkouts of the same repository instead of branches, and built no native MCP integration into OpenClaw, instead exposing MCPs as command-line tools through a separate converter — which he says needs no restart and scales better than the MCP approach used by Codex or Claude Code.
Make LLMs easy
  • LLM training tooling hasn't kept pace with the field and still breaks constantly. Drawing on three years training diffusion and language models, the speaker describes losing time to broken SDKs, GPU instances that fail only after a half-hour setup, and buggy open-source tools, and calls for better training APIs, large-dataset management tools and ML-native dev environments as post-training and model specialization grow in importance.
Infrastructure for Government Fraud Hunters
synopsis
  • Government fraud detection tooling is decades out of date. YC says most systems sold to agencies are rules engines from the mid-2000s with bolted-on machine learning, generating thousands of context-free alerts that humans end up ignoring; Medicare alone is cited as losing tens of billions of dollars a year to improper payments.
  • Qui tam whistleblower suits are the one mechanism that already claws back government money at scale, but the process is entirely manual. An insider tips off a law firm, which then spends years pulling documents and building a case; YC argues this should be software that parses messy PDFs and medical records, traces opaque corporate structures, and outputs lawyer-ready case files.
  • YC advises selling to intermediaries, not agencies, and wants founders who've done the work. Recommended first customers are whistleblower law firms, inspector generals, and state AG fraud units rather than big government agencies directly, with a founder profile that includes former False Claims Act counsel, healthcare compliance leads, or procurement auditors.
We're All Addicted To Claude Code
synopsis

On this Lightcone episode, host Garry Tan and the YC partners talk with Kelvin French-Owen — founder of Segment and an early builder of OpenAI's Codex — about becoming, in his words, newly "addicted" to Claude Code after years away from hands-on coding, and the conversation lands on a real fork between how Anthropic and OpenAI are building coding agents and what that implies for the future of software work.

From Codex to Claude Code. French-Owen recalls that at OpenAI he helped build Codex's web interface on the premise that coding would feel like delegating to a co-worker who returns with a pull request — a vision he still thinks is directionally right, even though the industry converged instead on terminal-based CLIs rather than IDEs or web views. He now uses Claude Code daily, having cycled through Cursor and other tools as the landscape shifted every few months.

Why the CLI works, and what makes Claude Code distinct. He argues CLIs won because they aren't tied to the file-exploration mental model of IDEs, giving agents more freedom, and Claude Code in particular splits tasks across "explore" sub-agents running smaller models in their own context windows before merging results — something he says Anthropic has tuned unusually well. He contrasts this with Codex's opposite bet: periodic compaction that sustains much longer, more autonomous runs, reflecting what he sees as Anthropic building collaborative "tools for humans" versus OpenAI pursuing longer-horizon, more independent model behavior in service of general intelligence.

The craft of using these tools well. The context window, he says, remains the binding constraint even now: he actively clears context around 50% usage to avoid a quality-degrading "dumb zone," and he describes builders planting an odd canary fact early in a session to detect when a model starts forgetting. He also credits a late push to 100% test coverage with a dramatic productivity jump, since the agent's own tests replaced most manual verification.

Distribution and the wider ecosystem. Both agree that bottoms-up, engineer-led adoption — no enterprise gatekeeping required — is reshaping which tools win, citing Supabase's disproportionate rise because well-documented open-source code is favored both by LLM recommendations and by agents reading a project's source directly.

Where this goes next. The conversation closes on speculation rather than certainty: French-Owen imagines a future of highly personalized software, where companies' internal tools are forked and edited live by individual employees' own coding agents, with humans retreating to access-control and judgment calls while agents handle execution. He predicts the most senior engineers benefit most today, since agents excel at converting a clearly specified idea into working code but still lack a reliable sense of good architecture — leaving direction-setting and taste as the durable human skills.

  • Claude Code's edge comes from splitting work across sub-agent context windows, reflecting a real architectural fork between labs. Kelvin French-Owen, who built Codex at OpenAI before founding Segment, says Claude Code spawns "explore" sub-agents running smaller models to search the file system in their own context windows before reporting back — while Codex instead runs periodic compaction to sustain much longer autonomous jobs, which he traces to Anthropic building "tools for humans" versus OpenAI pushing toward fully autonomous, longer-horizon models.
  • Context window size is still the top bottleneck, even for expert users, so managing it is an active skill. French-Owen says he manually clears Claude Code's context once it crosses roughly 50% token usage to avoid what he calls the "dumb zone" — a concept he credits to Dex at the YC company HumanLayer — where output quality degrades as the window fills; he also describes founders planting an odd "canary" fact early in a session to test when the model starts forgetting.
  • Building toward full test coverage sharply increased his coding speed. French-Owen says he worked with little to no testing for his first few days using Claude Code, then dedicated a day to reaching 100% test coverage, after which he rarely needed to manually verify changes because the agent's own test runs caught regressions — paralleling what the hosts say other teams have found doing test-driven prompt engineering outside of coding.
  • Bottoms-up, engineer-first distribution is reshaping which tools and even architecture choices win. French-Owen and the hosts argue coding CLIs succeed because individual engineers can download and use them without enterprise approval, and that open-source projects like Supabase benefit disproportionately because both LLM recommendations and coding agents reading source code directly favor visible, well-documented code over proprietary alternatives.
AI Guidance for Physical Work
  • Real-time AI guidance, not automation, is the near-term opportunity in physical work. For fields like field services, manufacturing, and healthcare where AI can't yet act in the world, the pitch is a worker wearing a camera while an AI sees what they see and talks them through the job step by step — "turn off that valve," "use the half-inch wrench," "that part looks worn, replace it."
  • The model is instant competence rather than months of training. With AI coaching in real time, YC argues a worker can be effective immediately and pull in new skills on demand instead of needing years of apprenticeship.
  • Three converging factors make this timely now: multimodal models that can reliably see and reason about real-world situations, hardware already in place (phones, AirPods, smart glasses), and skilled-labor shortages that make the problem economically urgent. YC suggests three possible approaches — selling to companies with existing workforces, building a full-stack vertical (e.g. HVAC repair or nursing), or a platform letting anyone become a skilled worker.
AI Powered Agencies
  • AI lets agencies flip from selling services to selling finished products at software margins. The speaker argues agencies can now use AI themselves to produce finished work upfront — a design firm pitching finished creative before a contract is signed, an ad agency generating video without a physical shoot, a law firm drafting documents in minutes — letting them charge far more and scale past the labor-bound limits of today's fragmented agency markets.
Cursor for Product Managers
  • AI coding tools solve building software, not deciding what to build. YC argues Cursor and Claude Code are good once it's clear what needs building, but the harder, more important work — talking to users, understanding markets, synthesizing feedback — still lacks an AI-native system covering the full product-discovery loop.
  • The pitch is a tool that turns customer data directly into a proposed feature. Upload customer interviews and usage data, ask what to build next, and get back a feature outline with a rationale grounded in that feedback, plus proposed changes to the UI, data model, and workflows.
  • The tool would also hand off directly to coding agents. It would break the proposed changes into development tasks sized for a coding agent to implement, reflecting YC's view that as agents take the first pass at implementation, how teams define and communicate what to build needs to change.
How We Redesigned Our Website
  • The old YC homepage read as generic and underplayed its own founders. YC's designer says the previous site felt like "a B2B SaaS template" with vague, unquantified claims ("we improve the success rate of our startups" without a number) and showed portfolio company logos without crediting the founders who built them — a gap the redesign set out to fix.
  • The redesign leans on storytelling rather than a sales pitch, drawing directly on Paul Graham's essays. The team studied PG's writing and pulled the word "formidable," which he and Jessica Livingston used for extraordinary early founders, into the new hero section, complete with a PG-style footnote defining it.
  • Founders, not YC, are put front and center. The new site shows before/after images of funded founders, side-by-side quotes stitched together from interviews with recent-batch founders about their YC experience, and photos of YC partners from when they themselves went through a batch — reinforcing that partners are ex-founders. The team deliberately kept most of the original circa-15-year-old PG homepage copy verbatim, updating only details like funding cadence and the San Francisco location.
  • The site was built by prompting Opus 4.5 in Cursor rather than designing static frames in Figma. The designer says this let the team prototype interactive sections live and iterate toward outcomes — like a scrolling before/after carousel — they don't think they'd have arrived at in a static tool, freeing their time to focus on storytelling and interaction design instead of manual implementation.
Why Your Startup Website Isn't Converting
synopsis

Reviewing five founder-submitted websites on this Design Review episode, Framer co-founder Jorn van Dijk keeps returning to one throughline: clarity about what the product actually does beats polish, and small unresolved details erode trust in everything else on the page.

Lumari, an AI procurement platform. Van Dijk says the heavy animation and vague icon graphics never anchor what the product looks like, and that its two "book a demo" CTAs ask for too much commitment before a first-time visitor understands the value; he recommends screenshots or a short walkthrough video instead.

"A lie," an AI presentation tool. He credits it with showing glimpses of the real interface rather than pure illustration, but flags that its highlighted customer quotes are too generic to back up a "high quality" claim, and that forcing signup before letting someone generate a presentation is a mistake given it's competing directly against a free incumbent, Google Slides.

Juicebox, an AI recruiting platform. Van Dijk likes its distinct visual identity and recognizable customer logos, but says its brutalist black-and-white style with a "win the talent war" tagline feels emotionally disconnected from being a product about finding people, and that its interactive demo hits a signup wall before delivering a payoff.

Leaping AI, a voice-AI call center replacement. He praises its live phone-call demo as genuinely persuasive, but notes the hero imagery of a single phone with one caller reads as consumer-facing even though the copy explicitly targets large enterprise call centers — a mismatch he says undercuts the positioning.

The Hog, a GTM automation tool. This gets the sharpest critique: unclear naming (an unexplained acronym), inconsistent spacing and typography, and testimonials with fully capitalized sentences and no attached company name, which together read as fabricated and cast doubt on the product's other claims. Van Dijk's closing advice, given the page's sprawl, is to strip it down to only what explains the product, test that stripped version on twenty people unfamiliar with it, and expand from there once comprehension is confirmed.

  • Generic illustrations of a product are a recurring failure across the sites reviewed, and screenshots or a short video would fix most of them. Framer co-founder Jorn van Dijk repeatedly tells founders (Lumari, the presentation tool "a lie") that vague icon animations don't tell a first-time visitor what the product does or looks like, and that a real screenshot or two-minute walkthrough would do more to earn trust than an abstract hero animation.
  • Asking for a demo or signup before showing any value creates unnecessary friction. Van Dijk argues a "book a demo" button is a big ask before a visitor understands what they're buying, and for the presentation tool competing directly with free Google Slides, he says letting people try the product immediately — even a prompt box on the homepage — matters more than gating access behind a signup wall.
  • Visual style needs to match what a site claims to be, or it undercuts the message. Van Dijk flags that Juicebox's black-and-white, "win the talent war" aesthetic feels disconnected from being a people-focused hiring product, and that Leaping AI's single-phone, consumer-style hero visual works against its stated positioning as an enterprise call-center replacement.
  • Small inconsistencies compound into distrust of a site's bigger claims. Reviewing The Hog, Van Dijk points to uneven letter spacing, a fully capitalized customer quote with no named company attached, and a shared toggle widget that behaves two different ways on the same page, arguing that a visitor who notices these details starts to doubt the numbers and testimonials elsewhere on the page too.
Building The World's First Reusable Rockets
  • They set out to build a fast-turnaround, fully reusable orbital rocket. The founders say the industry norm is to build and launch a rocket once, lose it in the ocean, and never see it again; they wanted a vehicle that reaches orbit, flies back, and repeats the cycle "again and again," a problem they felt nobody else was attacking with rigor.
  • Launching the company felt like an irresponsible, highest-stakes bet. One of the two co-founders calls starting from zero, with no one else in the field beside them, the hardest personal decision they've made, reached only once they concluded the idea "had to be tried" regardless of whether it succeeded.
The ML Technique Every Founder Should Know
synopsis

Visiting YC partner Francois Chaubard, who has worked in computer vision since 2012 and ran Focal Systems for a decade before returning to Stanford to finish a PhD on diffusion-based world models, argues diffusion is not just an image-generation trick but a general framework for learning any data distribution — one he believes founders training their own models should treat as a default tool, regardless of domain.

What diffusion is. Chaubard defines it as learning to reverse a noising process: take real data, progressively corrupt it with noise, then train a model to walk backward from noise to data. Its distinguishing strength is mapping low amounts of training data onto very high-dimensional outputs — he demonstrates learning a face distribution from only 30 sample images.

The objective got simpler, not more complex. Tracing the line from the original 2015 paper onward, he shows researchers found each successive prediction target easier to learn — first the data itself, then the added error, then a "velocity" — steadily cutting the Fréchet Inception Distance quality score from roughly 222 to about 8-10 today, while the code needed actually shrank, unusually for machine learning.

Flow matching as the current endpoint. He credits Meta's Yaron Lipman with reducing diffusion training to a straight-line velocity between noise and data, implementable in roughly five lines of code that transfer unchanged across images, proteins, DNA, or robot trajectories — the modeling architecture underneath is a separate, swappable choice.

Where it's deployed, and its limits. He cites DeepMind's Nobel-winning protein folding, diffusion robotics policies, and weather forecasting as proof points, noting diffusion has displaced most of AI except autoregressive language models and game-playing search. Its main limit: a model trained on a fixed number of denoising steps can't simply run more steps at inference for better quality.

  • Diffusion is a general-purpose way to learn any data distribution by training a model to reverse noise, and it now spans far more than images. Visiting partner Francois Chaubard cites DeepMind's Nobel Prize-winning protein-folding work, the "diffusion policy" approach used for robotics and self-driving, and Google's GenCast, which he calls the most accurate weather forecasting system in the world, as the same core mechanism applied to different domains.
  • Progress came from making the training objective easier to learn, not from a new core idea. Chaubard traces a line of papers that moved from predicting the noised data itself, to predicting the added error, to predicting a "velocity," each step making the math simpler and driving the Fréchet Inception Distance quality metric down from about 222 in the original 2015 paper to roughly 8-10 in modern models.
  • Flow matching, from Meta researcher Yaron Lipman, collapsed diffusion training into a straight line between noise and data. Chaubard demonstrates it as roughly five lines of training-loop code that work unmodified whether the underlying model is generating images, proteins, DNA, or robot trajectories, calling it one of the more profound simplifications in recent machine learning.
  • Chaubard's advice splits by role: model-trainers should treat diffusion as a default tool, and everyone else should update on how fast it's improving. He argues anyone training their own models should seriously evaluate diffusion regardless of application, and that non-trainers should expect roughly the same ~1,000x quality jump seen in image generation over five years (Midjourney to Sora/Veo/Flux) to extend into proteins, robotics policies, and self-driving as the technique keeps getting simpler.
The AI Economy Is Stabilizing
  • The AI economy stabilized into distinct model, app, and infra layers. A YC partner says 2025's biggest surprise was how much calmer things got compared to late 2024's rapid shifts, with a clear playbook now for building AI-native companies atop the models; he reads the stability as downstream of incremental model improvements rather than any single disruptive breakthrough this year.
How To Get Your First Users
  • Finding first users is a search problem, not a persuasion problem. Almost no one wants to be a startup's first customer, so the goal is finding the rare people who love trying new things or have a burning need — illustrated by the speaker paying and becoming the first customer of an unknown startup within three days because it solved a specific billing/API problem.
  • Charge real money early and use personal, targeted outreach. Early adopters and people with a burning problem aren't price-sensitive, and paying customers give sharper feedback than free ones; finding them looks like cold email or direct outreach, not mass channels like a billboard. The advice also includes launching early, studying early users like an anthropologist, and not fearing churn since a lost early user is low-stakes and easily replaced.
  • Personal software budgets are small, which shapes where AI founders sell. The speaker cites their own ~$150/month personal software spend versus multiple corporate tools each costing more than that alone, arguing this gap is why many AI founders target prosumers, businesses, or high-advertising-value users like doctors rather than pure consumers.
  • Build a "minimum evolvable product," not just an MVP, because early adopters steer what the product becomes. Using Tesla's Roadster as an example, the speaker argues early buyers who wanted an impractical, fast, tech-forward car — not comfort — are why the mass-market Model Y still has under-3-second 0-60 acceleration and worse suspension than a Toyota; product evolution is path-dependent on who adopts it first.
Inside The Startup Building Reusable Rockets
  • Stoke Space is targeting full rocket reusability, including the second stage that every other reusable rocket still throws away. A co-founder explains that industry has already made first-stage reuse routine, scaling launches from roughly 10-20 to about 150 a year, but the upper stage still burns up structurally around 2,700°F re-entering at 17,000 mph; Stoke's Andromeda capsule survives this with a heat shield cooled by liquid hydrogen and 24 small thrusters for landing.
  • The founders quit stable jobs at Blue Origin in 2019 to found the company on real personal risk. One co-founder describes it as "wildly irresponsible" and his hardest personal decision, having a 3-month-old at home; they set a 6-month deadline to find traction, got their first funding check right around that point, just as COVID hit, and built their first prototype engine in a shipping container in a backyard.
  • YC's network was central to raising capital in a market skewed toward SaaS. The founders say they wildly underestimated how hard fundraising would be as first-time hardware founders with no investor connections, and credit YC with teaching them the fundraising process and adding momentum to the round; the company has raised about $990 million to date.
  • Fast iteration is treated as the core competitive advantage, enabled by in-house manufacturing and custom software. By building nearly every part themselves rather than depending on outside suppliers, a co-founder says they cut a test-fail-rebuild cycle from about a month down to a day or two; the company also built its own operations software, called Bolt Line, to track part history and maintenance as it scales toward its first orbital launch, planned for later this year from a new site at Cape Canaveral.
The Truth About The AI Bubble
synopsis

Reviewing 2025 on the Lightcone podcast, the YC partners conclude the AI economy has stabilized into distinct, durable layers — models, applications, and infrastructure — each with a workable playbook, even as the details underneath shifted more than anyone expected.

A changing of the guard among models. Diana reports that in YC's Winter 2026 application data, Anthropic overtook OpenAI as founders' top API choice, after OpenAI held over 90% share in early batches and Anthropic hovered near 20-25% through most of 2024-25 before a recent surge past half. She credits Anthropic's internal focus on coding performance, plus a possible "bleed-through" from founders' own coding habits. Gemini has also risen sharply, from single digits to about 23%.

Model choice as arbitrage, not loyalty. Partners describe both consumers and founders treating models as interchangeable, hand-picking whichever performs best per task — one series-B company reportedly routes Gemini 3 for context engineering into OpenAI for execution — likening it to swapping chip architectures between Intel and AMD.

Reframing the bubble question. Drawing on economist Carlota Perez's installation-versus-deployment framework, the partners argue the massive current capex — data centers, power constraints prompting ideas like space-based data centers and fusion startups — sits on big incumbents' balance sheets, not founders', so a pullback wouldn't strand startups; the resulting compute glut instead sets up a deployment phase for application-layer companies, comparable to excess telecom fiber later enabling YouTube.

Fine-tuning's fading moat, and hiring. They note early fine-tuned "AI-headed" companies got overtaken once frontier models leapt ahead, though newer domain-specific fine-tunes on open-source bases can still beat general models narrowly. They also observe last year's zero-hire, high-ARR startups have mostly returned to normal hiring post-Series A, as rising customer expectations, not headcount efficiency, now seem to be AI tooling's dominant effect.

  • Anthropic overtook OpenAI as the top model choice among YC's Winter 2026 batch, a reversal from OpenAI's earlier dominance. Partner Diana says OpenAI held 90%+ share in early batches and Anthropic hovered near 20-25% through 2024 and early 2025 before surging past 50% in the last few months; she attributes it partly to Anthropic making coding performance an internal north-star eval, feeding the batch's wave of coding-agent and vibe-coding startups. Gemini has also climbed from roughly 2-3% to about 23% over the same period.
  • Founders increasingly treat models as commodity, interchangeable inputs rather than picking one loyally. Partners describe series-B-level founders building an orchestration layer that swaps models per task based on proprietary evals — one startup reportedly uses Gemini 3 for context engineering and feeds the result to OpenAI for execution — comparing it to how chipmakers Intel and AMD get swapped out as each releases a better architecture.
  • The "AI bubble" framing is reinterpreted through economist Carlota Perez's installation-versus-deployment model of tech revolutions. Partners argue the current heavy infrastructure capex — gigawatt data centers, and even fringe bets like space-based data centers and fusion-power startups such as Zephyr Fusion — sits on the balance sheets of big companies, not startups, so a slowdown there wouldn't strand founders; the resulting compute glut is framed as setting up the "deployment phase" for application-layer startups, comparable to how excess telecom fiber from the dot-com buildout later enabled YouTube.
  • Early fine-tuning-based moats are proving fragile against leapfrogging frontier models. Partners note a YC company that beat GPT-3.5 through fine-tuning was later "blown out of the water" once GPT-4.5 and 5.1 shipped, while newer domain-specific models fine-tuned with reinforcement learning on open-source bases can still beat general models on narrow tasks — one YC healthcare startup is cited as outperforming OpenAI's models on healthcare benchmarks with only an 8-billion-parameter model.
How Intelligent Is AI, Really?
  • ARC Prize defines intelligence as the efficiency of learning new skills, not the ability to execute known ones. Its president explains the foundation built on François Chollet's 2019 definition, contrasting it with benchmarks like MMLU that chase harder "PhD-level" problems; ARC tasks are deliberately kept solvable by ordinary people, testing whether a system can generalize rather than just score high.
  • Reasoning models produced a step-change on the ARC-AGI benchmark that pure pretraining never did. GPT-4's base model scored only about 4-5% as of 2024, but o1 and o1-preview jumped to roughly 21% once reasoning was introduced, which the foundation says is why OpenAI, xAI, Google, and Anthropic have all reported ARC-AGI scores for their frontier releases (Grok 4, Gemini 3 Pro/Deep Think, Opus 4.5) over the past 12 months.
  • The president warns against mistaking narrow RL-environment scoring for real progress. He argues that building a custom RL environment to ace a specific benchmark doesn't generalize the way humans do without one, calling it "whack-a-mole," and says ARC guards against this with a hidden test set and an emphasis on novel problems.
  • ARC-AGI-3, due next year, will be an interactive benchmark with no instructions and will score efficiency, not just accuracy. Test-takers must infer the goal of roughly 150 game-like environments purely from action and feedback, and performance will be normalized against average human action-counts rather than raw success rate. The president maintains that even a hypothetical 100% score would be necessary but not sufficient evidence of AGI, prompting further scrutiny of the system's remaining failure points rather than a declaration.
From Pivot Hell To $1.4 Billion Unicorn
synopsis

James Hawkins, CEO and co-founder of PostHog, walks through how a company now valued at $1.4 billion — 160 employees, roughly 300,000 customers, and 15-16 products in production or development — was built out of repeated failure, and lands on a conviction that the next leap is building AI that replicates entire job functions inside a company, not just features.

Pivot hell, literally. Hawkins and his co-founder quit stable jobs to bootstrap out of coffee shops, working through roughly one idea every five to six weeks. Their first attempt, a sales-territory management tool, drew fifteen interested prospects but only one ever clicked a signup link — a lesson, Hawkins says, that salespeople are unreliable signal because they're friendly on calls but don't follow through. A second pivot, a developer technical-debt survey tool, also failed to land. What worked was born from the pivots' own byproduct: exhausted from re-setting-up product analytics after every idea change, they built a self-hosted, open-source version aimed at engineers rather than product managers, reasoning that technical users' stated interest tracks their actual behavior far more closely.

Discipline over waiting for inspiration. Hawkins is emphatic that the team didn't wait to feel excited about an idea — they built things to discover excitement, holding themselves to weekly output goals and meeting every interested prospect in person, sometimes traveling long distances. Charging real money early, even for a $50/month product, gave them an unambiguous signal: if people wouldn't pay despite the founders' full effort, the idea wasn't solving a real problem.

A launch, then a brutal raise. The open-source analytics tool launched on Hacker News about a month before YC demo day and became, by Hawkins's account, the year's most-upvoted dev tool post there, flipping demand from push to pull overnight. But the timing coincided with COVID's onset in March 2020, and VC interest evaporated within a week; PostHog ended up raising via $5,000 angel checks after meeting some 160 firms for its seed round — the hardest fundraise in the company's history.

From scarcity to conviction. By contrast, the recent $75 million round at a $1.4 billion valuation, making PostHog YC's newest unicorn, came together after conversations with essentially one investor who'd offered to lead preemptively. Hawkins traces the round's ambition to a growing personal conviction, formed partly by reading about AI lab founders' original reasoning, that AI's capability gains won't plateau — pushing PostHog to attempt "product autonomy": a tool that scans session recordings, analytics, error tracking, and LLM traces across all its products and opens pull requests fixing issues automatically, aiming to build an AI equivalent of a role, product management, that already has proven market fit.

Standing out on purpose. Hawkins also credits deliberately "remarkable," polarizing marketing — absurdist billboards unconcerned with direct conversion and a sprawling, unconventional website documenting all 16 products, a developer-focused jobs board, and a public company handbook — with building the trust and attention a crowded, increasingly AI-saturated market demands.

  • PostHog's breakout product came directly from pain its founders caused themselves through repeated pivots. CEO James Hawkins says after a failed sales-territory tool (14 of 15 interested prospects never even clicked the signup link) and a failed developer-survey product, the team kept having to re-set-up product analytics after every pivot — leading them to build the self-hosted, open-source analytics tool that finally worked, on the insight that technical users make better early customers because "what they say is close to what they'll do."
  • Discipline, not inspiration, drove the search: charge money early and treat non-payment as your clearest signal. Hawkins says the team committed fully to roughly one idea every five to six weeks, meeting every interested prospect in person, and found that struggling to sell a $50/month product was as hard as the enterprise deals he used to close — proof the idea itself wasn't solving a real problem, since he knew they weren't holding back effort.
  • Fundraising flipped from brutal to easy over five years. The 2020 seed round coincided with COVID gutting VC interest overnight, forcing PostHog to raise via $5,000 angel checks after meeting roughly 160 firms; the recent $75 million round at a $1.4 billion valuation — making PostHog YC's newest unicorn — came together after talking to essentially one investor who'd offered to lead it preemptively.
  • The current bet is building AI that automates roles which already have product-market fit inside companies, starting with product management. Hawkins describes a "pull-based" tool in development that scans session recordings, analytics, error tracking, and LLM traces across PostHog's 15-16 products to open pull requests fixing issues automatically while engineers sleep, reasoning that if a human product manager role sells, an AI version of it should too.
Finding Opportunity in Outdated Rules
  • Many good startup ideas live in legal gray areas. He cites OpenAI's crawling of the entire web without permission as arguably fair use or "massive copyright theft," and recalls Lyft's founders fearing jail the week before launch, since what became Lyft and Uber was then effectively illegal.
  • Laws often get rewritten once consumers clearly benefit. He argues that finding laws written before a big tech shift, laws that no longer reflect reality, can be valuable for founders, since the legal environment tends to bend once it's clear the end user wins.
Inside The Startup Launching AI Data Centers Into Space
  • Orbital data centers could remove Earth's energy and water constraints on AI compute. Philip Johnston, co-founder of StarCloud, argues data centers in space draw constant solar power, radiate heat via infrared into deep space instead of evaporating fresh water, and can scale without land or grid limits, ultimately competing on cost with the largest terrestrial data centers.

  • A large, low-cost deployable radiator is StarCloud's core technical bet and IP. Johnston says the main public criticism, from a viral post by Andrew McCallip, is that dissipating heat needs impractically large surface area; he counters that co-founder Ezra, a satellite-structures PhD, is leading half the engineering team to just build that large radiator.

  • StarCloud pivoted from beaming solar power to Earth to sending data centers into orbit instead. Johnston says the team's original space-based-solar concept loses 95% of energy in transmission and only breaks even near $50/kg launch cost; recalculating for orbital data centers instead put breakeven near $500/kg, much closer to today's falling launch prices.

  • StarCloud built and launched its first satellite in 15 months, versus roughly 4 years for prior space startups. The company, backed by YC after a third application attempt (under its earlier name Lumen Orbit), launched its StarCloud 1 satellite with an Nvidia H100 GPU on November 2nd and plans a second, Blackwell-equipped launch in October 2026.