You asked about Open Source
43 people built something like it. 2 are gone.
That is 7% of the ones whose fate we could settle, against 23% across the whole register. 16 were acquired.
| Launched | What it was | Today |
|---|---|---|
| 2023-01-01 | Unified platform for secrets, certs, and privileged access management · infisical.com | still up |
| 2023-01-01 | YCFern Instantly offer SDKs and API Docs · buildwithfern.com | acquired |
| 2023-06-01 | YCTiptap The open-source document editor for humans and AI agents. · tiptap.dev | still up |
| 2023-01-01 | YCLangfuse Open source LLM engineering platform · langfuse.com | acquired |
| 2023-06-01 | YCTwenty Open Source CRM · twenty.com | still up |
| 2023-06-01 | YCParadeDB Unify application data, vectors, and full-text search in one Postgres · paradedb.com | still up |
| 2023-01-01 | YCLiteLLM Call every LLM API like it's OpenAI [100+ LLMs] · litellm.ai | still up |
| 2023-06-01 | YCrefine Open-source Retool for enterprise · refine.dev | still up |
| 2023-01-01 | YCReflex The operating system for building mission-critical enterprise apps. · reflex.dev | still up |
| 2023-06-01 | YCSkyvern Open Source AI Agent to automate browser workflows via an API · skyvern.com | still up |
| 2023-01-01 | Build and deploy fully‑managed AI agents and workflows · trigger.dev | still up |
| 2023-01-01 | Know what your LLM is doing — and why it’s failing · traceloop.com | acquired |
| 2023-01-01 | The SAFE for commercial contracts · commonpaper.com | still up |
| 2023-01-01 | The open source, fullstack monitoring platform: stop guessing why… · highlight.io | acquired |
| 2023-01-01 | YCNango A single API for all your integrations · nango.dev | still up |
| 2023-01-01 | YCUnify AI teammates for everyone else 🤖 · unify.ai | still up |
| 2023-01-01 | YCHelicone LLM Observability for Developers · helicone.ai | acquired |
| 2023-01-01 | YCRivet Rivet Actors are the primitive for stateful workloads · rivet.dev | still up |
| 2023-06-01 | Open source GenAI development platform · flowiseai.com | acquired |
| 2023-01-01 | YCKeep The open-source AIOps platform · keephq.dev | acquired |
| 2023-01-01 | YCOpenInt Open Source Embedded Product Integrations · openint.dev | acquired |
| 2023-01-01 | YCVocode Open source Voice AI · vocode.dev | acquired |
| 2023-06-01 | YCOpenPipe Turn expensive prompts into cheap fine-tuned models · openpipe.ai | acquired |
| 2023-06-01 | YCKhoj AI for humans · khoj.dev | still up |
| 2023-06-01 | YCHegel AI Open source tools for developing generative AI applications · hegel-ai.com | still up |
| 2023-01-01 | Open source tools & services for reliable AI Agents & AI Applications · dagworks.io | acquired |
| 2023-01-01 | YCArroyo Cloud-native stream processing · arroyo.dev | acquired |
| 2023-01-01 | YCMatano Cloud Native SIEM (alternative to Splunk/Elastic) · matano.dev | still up |
| 2023-06-01 | YCRecipeUI The open source Postman alternative. · recipeui.com | still up |
| 2023-06-01 | YCPeerDB Fast, native ETL for Postgres 🐘 🚀 · peerdb.io | acquired |
| 2023-01-01 | YCmoonrepo Open source build tool for monorepos and large codebases · moonrepo.dev | gone |
| 2023-06-01 | YCReworkd The simplest way to extract web data at scale · reworkd.ai | still up |
| 2023-06-01 | YCContinue Pioneering open-source coding agent · continue.dev | acquired |
| 2023-01-01 | YCKV Cash KV Cash, a blockchain where contracts can finally think · kv.cash | still up |
| 2023-06-01 | YCBolto AI Powered All-In-One Payroll, HR + Recruiting · bolto.com | still up |
| 2023-01-01 | Enterprise-Grade OpenTelemetry · odigos.io | still up |
| 2023-01-01 | YCHammr Rippling for the Construction Industry · hammr.com | still up |
| 2023-01-01 | Usage Metering, AI & API Monetization · openmeter.io | acquired |
| 2023-01-01 | AI-powered customer support automation for fast-growing companies · opensight.ai | gone |
| 2023-06-01 | The API for LLM tool use · opentools.com | still up |
| 2023-01-01 | Sales Agents with 100+ data sources to close more deals · persana.ai | acquired |
| 2023-01-01 | YCUnstatiq Single source of truth for your clinic's finances and supply chain. · unstatiq.com | still up |
| 2023-06-01 | Specialized agents for real work · opensteer.com | still up |
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.