You asked about Cybersecurity
Nobody in the register described anything this way.
| Launched | What it was | Today |
|---|---|---|
| 2020-06-01 | YCSafeBase Trust Center platform that scales customer security reviews · safebase.io | acquired |
| 2015-06-01 | Shifting the asymmetry of cyber security. · cymmetria.com | acquired |
| 2021-06-01 | YCTarsal Data pipeline for your security data lake. · tarsal.co | acquired |
| 2021-06-01 | YCTelivy Automate your cyber security risk assessments · telivy.com | acquired |
| 2021-01-01 | YCStacksi Automated Answers to Security Questionnaires · stacksi.com | acquired |
| 2023-06-01 | YCXeol Close your outdated dependency attack vector · xeol.io | acquired |
| 2015-01-01 | Cyberfend delivers robust, real-time web and mobile security by… · cyberfend.com | acquired |
| 2018-01-01 | YCHunter2 Hunter2 trains engineering teams in application security through… · hunter2.com | acquired |
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.