The Concentric design is originally from the Google Pixel Watch (1). This project recreates it using Watch Face Format.
The XML code can be found in the res/raw folder. Watch Face Format is well documented in case you wish to modify the watch face.
Google has transitioned to Gradle for compiling watch faces, but I still use the original build script provided when WFF first launched. For reference on building a watch face, see wear-os-samples/WatchFaceFormat.
To streamline the process, I’ve developed a small CLI tool that integrates this script, removing the need for Gradle. Once it's ready, I plan to publish it on GitHub.