I fine-tuned a 7B model to turn raw account data into structured JSON briefs.. it's up on Hugging Face, here's how it went and what I still haven't measured.
Data in an AI stack doesn't live in one place. It sprawls across caches, logs, vector stores, and traces. Residency is a surface, and you can't prove a surface from a diagram.
Everyone's composing small specialized models now, and everyone's moving them onto hardware they own. Almost nobody is measuring what happens when those two collide.