Install in three steps
Nimbus is a native Mac app. Download the beta, open it once, and drag it into Applications. The first launch needs one extra right-click — here's exactly what that looks like.
Download the beta
Grab the latest disk image from the Download for Mac button — or straight from GitHub Releases. The file is Nimbus-2.9.12.dmg.
Open the disk image
Double-click Nimbus-2.9.12.dmg. A small window opens showing the app icon next to the Applications folder.
The first time, macOS may say it can't be opened because the beta isn't notarized by Apple yet. That's expected — the fix is one step away:
xattr -cr /Applications/Nimbus.app, then open Nimbus
normally.
Drag into Applications
Drag Nimbus onto the Applications folder shortcut in the window. That's the whole install — open Nimbus from Applications or Launchpad whenever you want it.
Install on Windows
Nimbus for Windows needs Windows 10 (version 2004) or Windows 11. Most PCs want the standard download; Snapdragon and other ARM laptops want the ARM version.
Download for Windows ARM version
There is nothing to install: put Nimbus.exe wherever you like (Desktop or Documents) and double-click it. The island appears at the top of your screen and Nimbus sits in the system tray.