vcpkg/docs/users/config-environment.md

Environment and Configuration

Environment Variables

VCPKG_DOWNLOADS

This environment variable can be set to an existing directory to use for storing downloads instead of the internal downloads/ directory. It should always be set to an absolute path.

VCPKG_FEATURE_FLAGS

This environment variable can be set to a comma-separated list of off-by-default features in vcpkg. These features are subject to change without notice and should be considered highly unstable.

Non-exhaustive list of off-by-default features:

• binarycaching

EDITOR

This environment variable can be set to the full path of an executable to be used for vcpkg edit. Please see vcpkg help edit for command-specific help.

VCPKG_ROOT

This environment variable can be set to a directory to use as the root of the vcpkg instance. Note that mixing vcpkg repo versions and executable versions can cause issues.

VCPKG_DEFAULT_VS_PATH

This environment variable can be set to the full path to a Visual Studio instance on the machine. This Visual Studio instance will be used if the triplet does not override it via the VCPKG_VISUAL_STUDIO_PATH triplet setting.

Example: D:\2017

VCPKG_DEFAULT_TRIPLET

This environment variable can be set to a triplet name which will be used for unqualified triplet references in command lines.

VCPKG_FORCE_SYSTEM_BINARIES

This environment variable, if set, suppresses the downloading of CMake and Ninja and forces the use of the system binaries.