You asked about Open Source
Nobody in the register described anything this way.
| Launched | What it was | Today |
|---|---|---|
| 2015-01-01 | YCGitLab A complete DevOps platform delivered as a single application. · gitlab.com | acquired |
| 2013-06-01 | YCCoreOS Open source tools of modern distributed systems. · coreos.com | acquired |
| 2019-06-01 | YCEmbrace Modern user-focused observability built on OpenTelemetry · embrace.io | acquired |
| 2011-06-01 | Real-time. Big data. PostgreSQL · citusdata.com | acquired |
| 2020-01-01 | Run machine learning models in the cloud · replicate.com | acquired |
| 2023-01-01 | YCFern Instantly offer SDKs and API Docs · buildwithfern.com | acquired |
| 2019-06-01 | Spark-on-Kubernetes Data Engineering Platform · datamechanics.co | acquired |
| 2024-01-01 | YCOnyx Open Source AI Chat · onyx.app | acquired |
| 2023-01-01 | YCLangfuse Open source LLM engineering platform · langfuse.com | acquired |
| 2022-01-01 | Open-Source Postman alternative · requestly.com | acquired |
| 2019-06-01 | YCBun Bun is an incredibly fast all-in-one JavaScript toolkit · bun.sh | acquired |
| 2010-01-01 | YCZencoder Video Encoding API,
Open source video player (video.js) · zencoder.com | acquired |
| 2009-06-01 | The open source database for the realtime web. · rethinkdb.com | acquired |
| 2018-01-01 | CodeStream is a Developer Collaboration Platform designed to… · codestream.com | acquired |
| 2020-01-01 | DataOps Observability Platform for Snowflake · chaosgenius.io | acquired |
| 2023-01-01 | Know what your LLM is doing — and why it’s failing · traceloop.com | acquired |
| 2023-01-01 | The open source, fullstack monitoring platform: stop guessing why… · highlight.io | acquired |
| 2024-01-01 | YCTrieve All-in-one API for search, RAG, & recommendations · trieve.ai | acquired |
| 2022-01-01 | YCHydra Serverless Analytics on Postgres · hydra.so | acquired |
| 2023-01-01 | YCHelicone LLM Observability for Developers · helicone.ai | acquired |
| 2020-06-01 | YCFig Fig adds visual apps, shortcuts, and autocomplete to your terminal. · fig.io | acquired |
| 2021-01-01 | Open source continuous profiling software to debug performance issues · pyroscope.io | acquired |
| 2023-01-01 | YCKeep The open-source AIOps platform · keephq.dev | acquired |
| 2018-06-01 | YCOptic Making APIs Developer-friendly · useoptic.com | acquired |
| 2023-06-01 | Open source GenAI development platform · flowiseai.com | acquired |
| 2022-06-01 | YCHyperDX Open-source, dev-friendly observability. · hyperdx.io | acquired |
| 2024-01-01 | YCTusk AI agent that generates unit and integration tests · usetusk.ai | acquired |
| 2023-01-01 | YCOpenInt Open Source Embedded Product Integrations · openint.dev | acquired |
| 2020-06-01 | YCJitsu Open-Source CDP (acquired by Helium Ventures) · jitsu.com | acquired |
| 2015-06-01 | YCConvox Open-source tools for deploying, managing, and monitoring cloud… · convox.com | acquired |
| 2023-01-01 | YCVocode Open source Voice AI · vocode.dev | acquired |
| 2021-06-01 | YCBytebot Bytebot is the open source container for AI desktop agents. · bytebot.ai | acquired |
| 2021-06-01 | YCWarrant Authorization and access control as a service. · warrant.dev | acquired |
| 2022-06-01 | YCNeosync Neosync is an open-source anonymization and synthetic data platform. · neosync.dev | acquired |
| 2022-06-01 | YCPayload Developer-First Headless CMS and Application Framework · payloadcms.com | acquired |
| 2021-01-01 | Open source mobile marketing platform. Alternative to appcues /… · laudspeaker.com | acquired |
| 2023-06-01 | YCOpenPipe Turn expensive prompts into cheap fine-tuned models · openpipe.ai | acquired |
| 2014-01-01 | Open-source time-series data analytics extension for PostgreSQL · pipelinedb.com | acquired |
| 2023-01-01 | YCArroyo Cloud-native stream processing · arroyo.dev | acquired |
| 2020-06-01 | YCKeyDB The only database you'll ever need · keydb.dev | acquired |
| 2023-01-01 | Open source tools & services for reliable AI Agents & AI Applications · dagworks.io | acquired |
| 2023-06-01 | YCPeerDB Fast, native ETL for Postgres 🐘 🚀 · peerdb.io | acquired |
| 2023-06-01 | YCContinue Pioneering open-source coding agent · continue.dev | acquired |
| 2013-01-01 | YCZenefits HR for small businesses: onboarding, payroll and benefits. · zenefits.com | acquired |
| 2012-06-01 | YCLever Talent Acquisition Suite that combines ATS + Talent CRM · lever.co | acquired |
| 2017-01-01 | YCHumi Payroll, HR, and Health Benefits for Canada's SMB's · humi.ca | acquired |
| 2015-06-01 | Values based personalization at scale for asset and wealth management · openinvest.com | acquired |
| 2016-06-01 | YCWorkRamp The All-in-One Learning Platform · workramp.com | acquired |
| 2019-06-01 | YCLocalyze Global mobility platform for companies and employees · localyze.com | acquired |
| 2018-01-01 | The people, management, and culture operating system for your startup. · qulture.rocks | acquired |
| 2012-01-01 | YCFond Rewards and recognition SaaS for HR leaders · fond.co | acquired |
| 2015-01-01 | A better way to buy a home · openlistings.com | acquired |
| 2015-06-01 | YCEden Workplace software for people-centric companies. · edenworkplace.com | acquired |
| 2021-06-01 | YCDeed Making it easy for employees to donate and volunteer with good causes. · joindeed.com | acquired |
| 2019-06-01 | Learn from the experts at your company. · togetherplatform.com | acquired |
| 2014-06-01 | YCImpraise Enable managers to create an effective work environment for their team · impraise.com | acquired |
| 2018-01-01 | YCYouTeam We make it easy for startups to hire engineers. · youteam.io | acquired |
| 2022-01-01 | YCQuan End-to-end platform to improve wellbeing and team performance. · quanwellbeing.com | acquired |
| 2012-01-01 | YCMyVR The open platform for the vacation rental industry. · myvr.com | acquired |
| 2024-06-01 | YCCentral Payroll, benefits, state compliance & other bullsh*t for startups · centralhq.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.