You asked about Open Source
Nobody in the register described anything this way.
| Launched | What it was | Today |
|---|---|---|
| 2024-01-01 | YCOnyx Open Source AI Chat · onyx.app | acquired |
| 2023-01-01 | YCLangfuse Open source LLM engineering platform · langfuse.com | acquired |
| 2023-01-01 | Know what your LLM is doing — and why it’s failing · traceloop.com | acquired |
| 2023-01-01 | YCHelicone LLM Observability for Developers · helicone.ai | acquired |
| 2023-06-01 | Open source GenAI development platform · flowiseai.com | acquired |
| 2024-01-01 | YCTusk AI agent that generates unit and integration tests · usetusk.ai | acquired |
| 2021-06-01 | YCBytebot Bytebot is the open source container for AI desktop agents. · bytebot.ai | acquired |
| 2023-01-01 | YCVocode Open source Voice AI · vocode.dev | acquired |
| 2023-01-01 | Open source tools & services for reliable AI Agents & AI Applications · dagworks.io | acquired |
| 2023-01-01 | Usage Metering, AI & API Monetization · openmeter.io | acquired |
| 2023-01-01 | Sales Agents with 100+ data sources to close more deals · persana.ai | 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.