Field notes / 2026 · Trust
Why I left the platform for the patient
Twelve years building for billions taught me to feel scale in the abstract. I’m leaving for work where the consequence has a face, on purpose.
Live question
After a career of consequences measured in millions, do you want the kind you can finally see?
For twelve years my decisions reached people I would never meet — millions of parents, billions on a video platform, a child’s location request resolved or failed in seconds. You learn to hold that scale, but you hold it as math. A 2% regression is real, and it is also a number on a slide. The distance between the decision and the person it lands on is the entire design of the systems I’ve built.
The work I’m proudest of narrowed that distance on purpose. The consent ceremony for supervising a child’s existing account, with its two people, two devices, both physically present and either able to walk away, was an attempt to put a real human relationship, with its power imbalance, into software without flattening it. Account scoping is the same instinct expressed in infrastructure: the promise that this person’s life stays theirs. The thread through all of it was the stakes for the person at the edge of it, never the platform.
At platform scale you learn to feel a million people as a percentage. I want to feel them as one.
So I’m moving to trust-critical AI for healthcare, and I’m trying to be honest about why. Part of it is that the lessons transfer with uncomfortable directness. ‘Humans in the loop’ as theater, the demo that isn’t the product, the default that quietly decides something moral — those weren’t parental-controls problems. They were trust problems wearing a parental-controls costume, and they’re wearing a clinical one now, where being confidently wrong has a body attached to it.
The other part is harder to say without sounding sentimental, so I’ll say it plainly: I want the consequence to be legible to me again. Not a percentage I can defend in a review, but an outcome I’d have to look at. I don’t fully trust that motive — proximity to stakes can be its own vanity, and a healthcare logo doesn’t make anyone’s judgment better. What I do trust is the discomfort. The questions that kept me up building for children are the same ones waiting here, and I’d rather be kept up by them than learn, finally, to sleep.