3x founder

David Day

Building AI for Healthcare | YC Alum | Angel Investor

Co-founder

LunaBill· Fall 2025 🇺🇸 San Francisco, California, United States

in LinkedIn

2025Co-founder· LunaBill (YC F25)

Founder · since 2021

Company

LunaBill (YC F25)

Role

Co-Founder

current

Stage

—

no public source

Raised

—

no public source

Based

San Francisco, California, United States

current

Founder / co-founder — the company's markEmployee / research role

Source: LinkedIn work history

Profile coverage5 of 7 · missing posts, contact

LunaBill

AI Voice callers for healthcare billing teams

Fall 2025

Experience

Career

LunaBill (YC F25)
Co-founder
Co-Founder · San Francisco, California, United States · 2025 – Present
2025
Healthcare Financial Management Association (HFMA)
Member · California, United States · 2025 – Present
2025
Founders, Inc.
Fellow · San Francisco, California, United States · 2024 – Present
2024
University of California, San Francisco
Data Scientist · San Francisco, California, United States · 2023 – 2024
2023
Google Developer Student Clubs
Founder
Founder · San Francisco, California, United States · 2023 – 2024
2023
Skiesoft Corporation Limited
Founder
Founder · Taipei City, Taiwan · 2021 – 2023
2021

Bio

David previously founded Skiesoft, one of Taiwan’s biggest AI scribe company. He also worked at a data scientist at UCSF, building models to audit coding accuracy.