You asked about Recommendation System
240 people built something like it. 34 are gone.
That is 15% of the ones whose fate we could settle, against 23% across the whole register. 16 were acquired.
| Launched | What it was | Today |
|---|---|---|
| 2022-01-01 | YCShaped The real-time retrieval engine for search, feeds, and agents. · shaped.ai | still up |
| 2009-06-01 | FanChatter aggregates, amplifies and empowers fan content on every… · fanchatter.com | gone |
| 2009-06-01 | Product recommendations. · directededge.com | still up |
| 2023-01-01 | AI Powered Product Discovery · rubberduckylabs.io | gone |
| 2024-01-01 | A recommendation system for the Internet · browserbuddy.com | acquired |
| 2010-01-01 | The first all-in-one operating system for marketing · optimizely.com | acquired |
| 2017-06-01 | The first public safety operating system that eliminates crime. · flocksafety.com | still up |
| 2016-06-01 | YCAthelas Extensible, Integrated Technology that Simplifies Health Systems · athelas.com | still up |
| 2022-05-26 | vertigo.ai | unverified |
| 2020-01-01 | YCH1 Connecting stakeholders across the healthcare ecosystem. · h1.co | still up |
| 2022-05-23 | getnora.page | gone |
| 2022-06-03 | webosarchive.com | unverified |
| 2026-09-29 | space.bl2.net | unverified |
| 2024-01-01 | YCLegora The agentic operating system for legal work · legora.com | still up |
| 2022-03-24 | neverinstall.com | still up |
| 2022-11-24 | flowbite.com | still up |
| 2023-03-14 | modernfontstacks.com | still up |
| 2018-06-01 | YCSkydropX Logistic Management System for E-commerce & Retail in Mexico. · skydropx.com | still up |
| 2023-06-19 | hn-recommend.julienc.me | unverified |
| 2022-03-12 | system.com | still up |
| 2022-10-04 | optemization.com | still up |
| 2023-12-12 | aods.cryingpotato.com | still up |
| 2023-01-19 | jamsync.dev | moved |
| 2022-01-11 | supernova.io | still up |
| 2015-01-01 | YCQventus We automate operations for hospitals and health systems · qventus.com | still up |
| 2022-10-18 | lunchbox.io | still up |
| 2022-02-28 | firmbee.com | still up |
| 2022-05-24 | systemflow.co | unverified |
| 2021-07-17 | gorse.io | still up |
| 2022-05-07 | reshaped.so | still up |
| 2022-02-07 | abstractops.com | still up |
| 2022-05-20 | lettertribe.com | gone |
| 2022-05-05 | skill-focus.com | unverified |
| 2016-01-01 | Building the Operating System for B&M Retail using Deep Learning · focal.systems | still up |
| 2022-04-17 | eccco.space | unverified |
| 2021-11-27 | mood2movie.com | still up |
| 2022-10-30 | thevcos.com | still up |
| 2020-01-01 | We are connecting every single Mexican to the financial system. · fondeadora.com | still up |
| 2021-01-01 | YCEstoca The Logistics Operating System for E-commerce in LatAm · estoca.com.br | still up |
| 2013-06-01 | YCCoreOS Open source tools of modern distributed systems. · coreos.com | acquired |
| 2023-04-12 | librarian-ai.com | still up |
| 2023-08-15 | servicer.dev | still up |
| 2022-07-06 | cred.club | still up |
| 2022-04-05 | getvivid.app | still up |
| 2019-06-01 | Helping create a smaller, fairer, safer justice system · recidiviz.org | still up |
| 2022-03-09 | cabanaui.com | still up |
| 2021-01-01 | YCgaiia all-in-one operating system (OS) for telcos · gaiia.com | still up |
| 2021-11-23 | tamagui.dev | still up |
| 2022-01-01 | AI-native operating system for home service businesses · broccoli.com | still up |
| 2023-06-01 | The World's First Multi-Agent System for Procurement · lio.ai | still up |
| 2022-01-01 | Robots for longer-lasting, better-tasting fish at scale. · shinkei.systems | still up |
| 2018-01-01 | YCPromise Better payment systems for governments and the communities they serve. · promise-pay.com | still up |
| 2022-06-16 | lockable.dev | unverified |
| 2023-05-22 | wiktok.org | moved |
| 2018-01-01 | The people, management, and culture operating system for your startup. · qulture.rocks | acquired |
| 2017-06-01 | LTSE is an ecosystem for visionary business. · ltse.com | still up |
| 2020-01-01 | YCWonderly Closed-loop end-to-end AI System that recursively improves on… · usemotion.com | still up |
| 2023-06-01 | The operating system for inbound B2B revenue · hockeystack.com | still up |
| 2026-10-19 | 3anddoneapp.com | unverified |
| 2021-06-01 | YCDatlo Datlo helps companies increase sales and expand through data · datlo.com | still up |
How this compares
Y Combinator reports its own outcomes, including acquisitions. The other two are judged by asking the domain, so they are not measured the same way and are never averaged together.
Older launches have had longer to die, so this slope is expected. A year that broke it would mean something is wrong with the checking.
The register re-probes every domain it holds. Some that answered last month stop answering. We send that list — what went quiet, and what it was — once a month. Nothing else.
How this was made. Show HN entries are every post from 2021 to 2023 with at least five points that linked to its own domain; code hosts and free hosting are excluded, because a repository outlives the effort behind it. Product Hunt entries needed 100 votes — a far higher bar, so they are the promoted top slice rather than a like-for-like sample. Both are judged by asking the domain whether it still answers: gone means it no longer resolves, refuses the connection, serves a parking page, or says plainly that it shut down. An HTTP error is not counted as gone — a server answering 404 is one somebody still pays for, and an audit of 25 gone-calls found two such sites alive with only a moved homepage. Y Combinator entries use the status YC publishes itself, which is why only those can say acquired. Squatted domains — a lapsed name now serving somebody else's site — are not detected, so these figures run slightly low.