Upgrading butler
Since butler is a single executable file, you can always upgrade it at any time by downloading a newer version (from the links given in the Install page) and replacing your current version with it.
However, the butler upgrade
command provides an easier way to upgrade
to a newer version.
When running network commands like butler push
or butler status
,
butler will run a version check in the background, and display a notice
if one is available: