You asked about Quantum Computing
12 people built something like it. 12 are gone.
That is 100% of the ones whose fate we could settle, against 23% across the whole register.
| Launched | What it was | Today |
|---|---|---|
| 2019-01-01 | YCAuroraQ Building the first practical, integrated quantum computer. · auroraq.com | gone |
| 2016-06-01 | YCSixa Personal computer in the cloud · sixa.io | gone |
| 2022-06-01 | No-code data curation for LLM fine-tuning and evaluation. · airtrain.ai | gone |
| 2021-01-01 | YCTriplit The best database for app developers · triplit.dev | gone |
| 2012-06-01 | YCGoScale Dynamical Scaling Virtual Machines as a Service · goscale.com | gone |
| 2024-06-01 | Software and hardware to run neural networks faster and cheaper · deepsilicon.net | gone |
| 2012-06-01 | Helping developers scale their applications with ease. · paralleluniverse.co | gone |
| 2019-06-01 | YCTensil We turn machine learning models into custom hardware. · tensil.ai | gone |
| 2013-06-01 | Instant sandboxed server environments · stackmachine.com | gone |
| 2023-01-01 | YCCakework API that adds cloud hosting to any developer platform · cakework.com | gone |
| 2024-01-01 | YCCelest The Vercel of Flutter · celest.dev | gone |
| 2011-01-01 | .NET Cloud Platform as a Service · appharbor.com | gone |
How this compares
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.