Design around the dependency.
The demo packages a dataset license, GPU capacity, and an independent evaluation. A buyer assembles the package; each provider sees and accepts its own leg. The interface makes a shared outcome visible without exposing everyone else's commercial terms.
Prove the all-or-nothing promise.
On September 30, the current Daml contracts compiled and passed atomic-success, rejection, and private-terms tests. A temporary Canton sandbox JSON API run created three active reservations in one settlement update. A rejection path did not activate the package.
The deployment setback belongs in the story.
On October 1, a restarted file-backed sandbox could not complete transaction submission. It was stopped rather than connected to the public app. The successful isolated proof remained useful, but it did not become evidence of a public Canton-connected transaction.