There are several shell environment variables that you can use to customize the Rush tool’s behavior.
This variable overrides the temporary folder used by Rush. The default value is “common/temp” under the repository root.
This variable overrides the version of Rush that will be installed by the version selector. The default value
is determined by the
rushVersion field from rush.json.
For example, if you want to try out a different release of Rush before upgrading your repo, you can assign the variable like this:
$ set RUSH_PREVIEW_VERSION=5.0.0-dev.25 $ rush install
This variable selects an alternate installation variant for Rush to use when installing and linking package dependencies. For more information about this feature, see Installation Variants.