Build vs buy your accounting AI stack: part 4, the market answered
BILL is repricing AI-agent work from seats to consumption, Xero says one in five ecosystem connections is now a custom-built app, and frontier model prices dropped again. Part 4 of Buy vs. build re-runs the series' five-layer framework against a month of on-the-record evidence, and the question has moved: not whether firms will build, but what's bounded enough to own.
