You asked about Reinforcement Learning
64 people built something like it. 64 are gone.
That is 100% of the ones whose fate we could settle, against 23% across the whole register.
| Launched | What it was | Today |
|---|---|---|
| 2016-01-01 | YCPathmind Pathmind helps industrial engineers and simulation modelers achieve… · pathmind.com | gone |
| 2025-06-01 | YCNuntius Making Models Follow Rules. · nuntius.ai | gone |
| 2025-09-01 | YCSylvian Specialized AI Agents. · sylvian.ai | gone |
| 2022-04-12 | damnnnn.com | gone |
| 2022-05-10 | getindx.com | gone |
| 2022-01-01 | YCAntWalk An employee up-skilling platform for fast growing companies · antwalk.com | gone |
| 2018-01-01 | Engineering next-generation, brain-penetrant cancer therapies. · reverielabs.com | gone |
| 2021-06-01 | YCAkudo India's first learning-focused neobank for teenagers · akudo.in | gone |
| 2022-08-04 | app.learningloop.org | gone |
| 2021-01-01 | Embed NL-to-SQL into your Product 📈 · dataherald.com | gone |
| 2021-01-01 | YCInvoid Create identity verification workflows the way you want · invoid.co | gone |
| 2021-01-31 | hacker-ai.com | gone~60mo |
| 2024-01-01 | Open-source humanoid robots · kscale.dev | gone |
| 2019-01-01 | AI-powered corporate learning for accelerated employee growth & skill… · tailor-ed.com | gone |
| 2020-01-01 | YCSprintAI AI-led platform for inventory and fulfillment optimization · getsprint.ai | gone |
| 2021-03-02 | blog.repl.it | gone~8mo |
| 2015-01-01 | Buid, test and deploy perception applications · standardcyborg.com | gone |
| 2022-01-01 | YCFlike Flike's AI crafts sales emails that convert · flike.app | gone |
| 2023-01-01 | The TikTok style corporate training platform · goodcourse.co | gone |
| 2023-04-28 | sotai.ai | gone |
| 2020-01-01 | We generate synthetic data for computer vision models. · zumolabs.ai | gone |
| 2021-06-01 | YCSpoken Never overpay online · spoken.io | gone |
| 2017-01-01 | YCEntry Biometric sign in and identity verification platform · getentry.com | gone |
| 2019-01-01 | Large Scale Genomic Data Mining Software · spiralgenetics.com | gone |
| 2022-01-01 | YCPloomber Heroku for AI · ploomber.io | gone |
| 2021-10-05 | odysseyapp.co.nz | gone |
| 2018-01-01 | YCVathys Accelerating machine learning through software · vathys.ai | gone |
| 2023-01-01 | YCLuca The Modern Pricing Engine for Retail · askluca.com | gone |
| 2022-01-01 | Promotion management platform · cherry.ai | gone |
| 2021-01-01 | YCPrendea Live afterschool classes for Spanish-speaking kids ages 4 to 15. · prendea.com | gone |
| 2021-06-01 | Building Gong.io for offline retail. · outloud.ai | gone |
| 2021-01-01 | Synthetic data for better vision. · sbxrobotics.com | gone |
| 2020-06-01 | The "Shopify" for Online Schools · tryvirtually.com | gone |
| 2022-08-05 | pledu.co | gone |
| 2020-06-01 | Demand Forecasting as a Service · intelligent.services | gone |
| 2019-06-01 | Hearing aids that work in noisy places, like restaurants, using ML. · audiofocus.io | gone |
| 2021-01-01 | We teach Filipinos to become remote software engineers globally. · avionschool.com | gone |
| 2017-01-01 | YCFloydHub ML Platform for developing, training and deploying ML models · floydhub.com | gone |
| 2021-01-01 | Breaking new ground in online eyecare. · quadranteye.com | gone |
| 2020-01-01 | Create active, collaborative learning experiences · clayboard.com | gone |
| 2022-06-01 | YCCAPSULE Buy anything you find on social media · shopcapsule.ai | gone |
| 2023-01-01 | AI for drug formulation · lavo.ai | gone |
| 2019-06-01 | Turn any website into an API · dashblock.com | gone |
| 2014-01-01 | Mobile keyboards + emoji + deep learning. We make Dango. We also made… · getdango.com | gone |
| 2021-06-01 | YCBuzzle Automatic voice-of-customer trends & metrics from sales conversations. · buzzle.ai | gone |
| 2020-01-01 | YCOrbiter ML models automatically monitor business performance · getorbiter.com | gone |
| 2021-06-01 | Observability for Data Engineering Teams · lariatdata.com | gone |
| 2012-01-01 | YCMarft Marft creates embeddable machine learning models for application… · marft.com | gone |
| 2018-01-01 | YCVoicery Automated voice acting and emotive speech synthesis with deep neural… · voicery.com | gone |
| 2017-01-01 | YCCowlar Fitbit for dairy cows. Farms use cowlar's alerts & recommendations to… · cowlar.com | gone |
| 2019-06-01 | YCTensil We turn machine learning models into custom hardware. · tensil.ai | gone |
| 2015-06-01 | Building the lowest-power silicon for embedded deep learning and… · remicro.com | gone |
| 2014-06-01 | Intelligent Lead Sourcing · salessift.com | gone |
| 2013-06-01 | YCCrowdery [Now Clara, YC S14- claralabs.com] · crowdery.com | gone |
| 2024-09-01 | AI Co-Pilot for Design · supercontrast.com | gone |
| 2021-01-01 | Create video testimonials with a link · milkvideo.com | gone |
| 2024-01-01 | YCPreloop Translate your experimental scripts into production ML services · preloop.com | gone |
| 2023-06-01 | Affordable carbon tracking solution for all businesses · greentally.ai | gone |
| 2022-01-01 | YCLifecast Software to create 3D video for VR, robotics and film. · lifecastvr.com | gone |
| 2024-09-01 | Pushing the boundaries of AI · zeroframe.ai | gone |
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.
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.