co-founder of lunabill (YC F25) & running formosa founders house

Joined December 2021
7 Photos and videos
David Day retweeted
Apr 15th inviting 500 founders into a discord server only for builders who have a nothing to lose mentality, no plan B, will work after hours & want to build something massive next to others like them by end of may you will have a company applications are open!
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David Day retweeted
Roy is right. The institutions need to change. It’s not fair to shame the people who have to go through the doors. Sorry.
Replying to @garrytan
“bring back integrity” but “the problem isn’t 18-year-olds gaming incentives” so which is it, do u think gen z/alpha don’t have any integrity or do u think some systems are just designed to fail? if 40% of stanford undergrads are claiming disability, the obvious solution is to rework the disability system entirely, not to shake ur first at the sky about how young’uns have no morals. do we solve the obesity problem in america by crying about “bringing back hard work” or do we try and stop putting fucking twinkies in every grocery store? the brutal truth pill i think u and everyone else >25 need to take is that the number of (otherwise integrity-having) young kids cheating in school is not some reversible 10%. it’s closer to 95-99%. so sick of hearing old techies complain ab morals when the actual answer is that u just have to completely rebuild most systems YOU guys put into place
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David Day retweeted
how do i get the most "real" builders in one place? no bs, no twitter hype, only focused on awesome projects with progress ill make top comment happen irl
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David Day retweeted
16 Dec 2025
Introducing Artifact Our largest program ever 200 founders. $2 million to top teams. 5 weeks on our campus in San Francisco. Applications are open. Early decisions Dec 20 GO!
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David Day retweeted
20 Nov 2025
dec 3rd inviting 30 founders to grind through the holidays only for builders who have a nothing to lose mentality, will pull late nights, & want to build something massive next to others like them by dec 31st you will have a company applications are open!
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20 Nov 2025
RT @jamesfong: 🩺 @getlunabill (YC F25) is building AI voice callers that take on the most painful part of healthcare billing: insurance cla…
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David Day retweeted
🚀 YC F25 is HERE — and I just published the full breakdown you’ve been waiting for. After weeks of 1:1s with founders and deep dives into the batch, I pulled together: 🔥 The entire YC F25 startup list 📊 Category breakdowns % share 🤖 Theme analysis (spoiler: AI is still everywhere) 🧠 Insider look at which YC partners backed what ⭐ And our top favorite companies of the batch If you’re an investor, founder, or just YC-curious, this is the most comprehensive look at F25 anywhere. 📩 Want to read the full analysis download the complete list? Comment "YC" and I'll send it to you ⚡ Curious what surprised us most this cycle? Why certain founders are breaking out? Or which categories YC partners are really leaning into? Drop a comment!
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David Day retweeted
Lunabill (@getlunabill) is the AI call center for healthcare billing teams. They've already partnered with leading US healthcare systems to automate 50,000 phone calls, saving them over 20,000 hours.
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David Day retweeted
Lunabill is automating one of the most time-consuming, manual processes in healthcare – billing teams making endless calls to sort out issues. They’re winning big deals because their product is perfectly tuned to solve this. Congrats @bitcoinbasha @internetskating @daviddaytw!
Lunabill (@getlunabill) is the AI call center for healthcare billing teams. They've already partnered with leading US healthcare systems to automate 50,000 phone calls, saving them over 20,000 hours.
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28 Jul 2025
Using Gmail’s AI to polish a simple email and it gave me... this. 😭 Did I unlock a hidden sci-fi writer prompt or join a secret government satire project?? (My original message was totally normal, I swear.)
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David Day retweeted
we’ve built the most realistic AI caller for healthcare - less than 2% detection as AI - an 97.67% success rate across 30k calls here’s how we achieved it:
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David Day retweeted
ever wanted to automate your craziest manual workflows? here’s a thread on every tool we tried and what we learned. 👇
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David Day retweeted
21 Apr 2025
The VC world has made a misstep Introducing the world's largest founder campus
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David Day retweeted
When a 2D game works in 4D.
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NEED HELP!
My repo just reached 50 organic stars with just 1 alpha version released. Is anyone experienced with Expo interested in helping grow a mobile local LLM library? #reactnative #Expo
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My repo just reached 50 organic stars with just 1 alpha version released. Is anyone experienced with Expo interested in helping grow a mobile local LLM library? #reactnative #Expo
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David Day retweeted
These founders are NOT done with 2024. Just completed our group office hours and grinding hard.
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25 Dec 2024
Merry Christmas! 12/25=0.48 #MerryChristmas #mathematics
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