You asked about Developer Tools
127 people built something like it. 0 are gone.
That is 0% of the ones whose fate we could settle, against 23% across the whole register.
| Launched | What it was | Today |
|---|---|---|
| 2016-01-01 | YCDaily Conversational Voice and Multimodal AI built with Open Source · daily.co | still up |
| 2020-01-01 | YCAirbyte Context layer for production-grade AI agents · airbyte.com | still up |
| 2021-06-01 | YCRootly AI-native on-call and incident response carefully crafted to help… · rootly.com | still up |
| 2021-06-01 | YCAnakin One API to get clean data from any website for your AI agents at scale · anakin.io | still up |
| 2017-06-01 | The best way to build Voice AI apps · assemblyai.com | still up |
| 2020-01-01 | YCTermii Termii is an AI-native reliability infrastructure company. · termii.com | still up |
| 2021-01-01 | YCMindee AI Document Understanding API · mindee.com | still up |
| 2021-01-01 | YCVapi Voice AI for developers. · vapi.ai | still up |
| 2021-09-07 | blog.spiceai.org | still up |
| 2022-01-01 | YCBotCity Observability and Governance for AI-Generated Python scripts. · botcity.dev | still up |
| 2022-01-01 | YCUnlayer AI-powered content creation infrastructure for apps · unlayer.com | still up |
| 2024-01-01 | YCGreptile AI code review agent with complete context of your codebase · greptile.com | still up |
| 2021-01-01 | YCauthzed Authorization Infrastructure securing AI at OpenAI, Zoom, & more · authzed.com | still up |
| 2025-01-01 | YCMastra The Javascript framework for building AI agents, from the Gatsby devs · mastra.ai | still up |
| 2017-06-01 | YCD-ID Enable creators and developers to generate realistic AI personas · d-id.com | still up |
| 2021-06-01 | The fastest way to ship airtight AI · openlayer.com | still up |
| 2021-01-01 | YCOpenCode The open source AI coding agent · opencode.ai | still up |
| 2024-01-01 | YCRespan Open-source, extensible AI gateway with observability and evals · respan.ai | still up |
| 2015-06-01 | AI-assisted electronics design · snapmagic.com | still up |
| 2025-06-01 | YCKERNEL Crazy fast, open source infra for AI agents to use the Internet · kernel.sh | still up |
| 2022-06-01 | YCAxle AI-native clearinghouse for insurance · axle.insure | still up |
| 2023-06-01 | YCTiptap The open-source document editor for humans and AI agents. · tiptap.dev | still up |
| 2023-01-01 | YCInkeep Build AI Agent teammates and automations in code or no-code · inkeep.com | still up |
| 2024-06-01 | YCWordware AI agents you can rely on · wordware.ai | still up |
| 2024-01-01 | YCMomentic Mo, the AI QA engineer that bug-bashes your app before every release · momentic.ai | still up |
| 2024-09-01 | YCCekura Voice AI and Chat AI agents: Testing and Observability · cekura.ai | still up |
| 2021-06-01 | AI SDET for mobile apps · mobileboost.io | still up |
| 2022-06-01 | YCIntuned Code-first scrapers and RPAs — built and maintained by AI · intunedhq.com | still up |
| 2021-01-01 | YCweweb.io WeWeb is the AI app builder your IT team will approve. · weweb.io | still up |
| 2021-06-01 | YCDailybot Make all team work visible — people and AI agents · dailybot.com | still up |
| 2024-09-01 | YCArchil The high-performance file system that connects AI to data · archil.com | still up |
| 2025-06-01 | Email Inboxes for AI Agents · agentmail.to | still up |
| 2024-01-01 | YCZep AI The unified context layer for enterprise data · getzep.com | still up |
| 2024-06-01 | YCCoval Simulation & Evaluation that scales voice and chat AI agents · coval.dev | still up |
| 2024-06-01 | YCMem0 The Memory layer for AI Agents · mem0.ai | still up |
| 2022-06-01 | YCLamin Open data platform for traceable, multimodal AI · lamin.ai | still up |
| 2019-06-01 | Vibe code games. · rosebud.ai | still up |
| 2023-01-01 | YCBoundary The programming language for AI · boundaryml.com | still up |
| 2023-01-01 | YCLiteLLM Call every LLM API like it's OpenAI [100+ LLMs] · litellm.ai | still up |
| 2025-06-01 | Persistent computers for AI agents · dedaluslabs.ai | still up |
| 2023-01-01 | Build and deploy fully‑managed AI agents and workflows · trigger.dev | still up |
| 2024-06-01 | Open-Source Reinforcement Learning (RL) & Fine-tuning for LLMs. · unsloth.ai | still up |
| 2020-01-01 | YCSignadot Scalable validation infrastructure for AI agents · signadot.com | still up |
| 2026-06-01 | AI engineer that debugs and fixes production incidents in realtime · hyperprobe.co | still up |
| 2023-06-01 | YCTempo Visual Editor for React, powered by AI · tempo.new | still up |
| 2025-06-01 | YCLuminal Making AI run fast on any hardware. · luminal.com | still up |
| 2024-09-01 | YCInnate Personal AI Robots · innate.bot | still up |
| 2025-01-01 | Production Monitoring & Evals for AI Agents · confident-ai.com | still up |
| 2025-06-01 | YCEmbedder Hardware-Aware AI for Embedded Software · embedder.com | still up |
| 2024-06-01 | YCLaminar Understand why your AI agent breaks. Iterate fast to fix it. · laminar.sh | still up |
| 2022-01-01 | No-Code LLM Application / Workflow Builder · queryvary.com | still up |
| 2025-06-01 | YCLark The E2E testing layer for AI-driven development · getlark.ai | still up |
| 2019-01-01 | YCCosmic Cosmic is an AI-powered headless CMS · cosmicjs.com | still up |
| 2025-06-01 | YCAutosana AI agents for E2E testing across mobile & web · autosana.ai | still up |
| 2023-06-01 | YCCedana Fast, reliable, reproducible AI with GPU live migration · cedana.ai | still up |
| 2024-06-01 | YCHeroUI The UI framework for AI agents and developers to build beautiful apps. · heroui.com | still up |
| 2024-06-01 | The most powerful sandboxes for AI Agents · freestyle.sh | still up |
| 2025-01-01 | An AI teammate that automatically updates your customer-facing docs · promptless.ai | still up |
| 2024-01-01 | Helps teams work effectively with AI coding agents. · centauri-ai.tech | still up |
| 2025-09-01 | YCMoss Real-time semantic search for Conversational AI · moss.dev | still up |
How this compares
Y Combinator reports its own outcomes, including acquisitions. The other two are judged by asking the domain, so they are not measured the same way and are never averaged together.
Older launches have had longer to die, so this slope is expected. A year that broke it would mean something is wrong with the checking.
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.