Keyboard shortcuts

Every shortcut in System Settings › Keyboard › Keyboard Shortcuts… is an option: false turns it off, true turns it on with its default keys, and a string sets your own keys, written the way macOS shows them:

keyboard.keyboardShortcuts = {
  spotlight.showSpotlightSearch = false;
  screenshots.copyPictureOfSelectedAreaToTheClipboard = "⌘⇧S";
  windows.fill = "⌃⌥Return";
};

Keys are any of ⌃ ⌥ ⇧ ⌘, in any order, followed by one key:

Key	Write it as
Letters, digits, punctuation	A, 7, /, -… (US layout)
Arrows	← → ↑ ↓
Function keys	F1 … F20
Others	Space, Return, Tab, Delete, Escape, Home, End, PageUp, PageDown, ForwardDelete

Shortcuts take effect straight away, without logging out.

App shortcuts

Keys for any app’s menu items, like Keyboard Shortcuts… › App Shortcuts. A menu item in a submenu is written with its menus:

keyboard.keyboardShortcuts.appShortcuts.menuItems = {
  "com.apple.TextEdit"."Format->Make Plain Text" = "⌘⇧T";
  "All Applications"."Show Help menu" = "⌘⇧/";
};

Each app you list gets exactly those shortcuts; apps you leave out keep theirs.