What they did
The poster, u/abdenourgnx1, had a 7th generation Kindle sitting unused. They jailbroke it by hand first, following the kindlemodding.org guide, because Claude would not help edit the device until that was done, and installed KUAL, the Kindle app launcher. From there Claude did the design and the build: the poster gave it a concept image of the screen they wanted and described how it should behave, and Claude wrote the app that runs on the Kindle and pulls its data over Wi-Fi. In the comments the poster says Claude also proposed a train timetable view built on their local public transport company's API.
How it went
The dashboard runs on the Kindle and refreshes once an hour. The first version drained the battery too fast, so the poster had the update loop reworked: the screen sleeps between updates, Wi-Fi switches on only while fetching, and nothing runs overnight. With that, battery drain came down to about 10% a week. The post has no code and no breakdown of how long the build took.
Worth knowing
The jailbreak is a manual step you do yourself, and it depends on your Kindle model and firmware. A commenter suggests rendering the whole screen as one image on a server so the Kindle only downloads and shows it, and forcing a full e-ink refresh every few updates to avoid ghosting. The poster did not say which Claude product or harness did the work.