Built by an MD who ran a gym.
Mauro Castillo · Founder, Cero To AI
I opened a gym in 2020. By 2022 I was first in, last out. Answering DMs at 11 PM. Missing calls during morning class. Forgetting to follow up with the lead from Tuesday.
I did what everyone told me to do. Hired a front desk person. Bought the software. I still drowned.
My team did their jobs. The software did its job. The pieces never connected. Every part of running a gym that should have been a system was being held together by my memory and my late nights.
So I built Cero OS™. One system that does the work I wish someone had done for me, so the next gym owner doesn't lose Saturdays to admin and Sundays to guilt.
- Doctor of Medicine
- Master of Science, Sports Training
- CSCS, Certified Strength & Conditioning
- Former gym owner (2020–2022)