Get dux from the Mac App Store, or as a direct download from this site. Both are free, and Pro bought in the App Store works in both.
For most people. Free, with Pro bought in the app with your Apple Account. Updates through the App Store. It runs in Apple's sandbox: you pick the disks and folders it may read, and it does not run tool cleanups such as Homebrew's or Xcode's.
The App Store page is not live yet.
For developers, power users and organizations. The same app plus tool cleanups, Full Disk Access, the command line tool and Business. Signed with our Developer ID and notarized by Apple, and it updates itself. Pro is a license key from this site, and Pro bought in the App Store works here too, on the same Mac.
The direct download is not available yet.
Not sure which one to pick? The free plan is complete in both. App Store or direct download compares them side by side and explains how to move from one to the other.