CMAKE_DEFAULT_BUILD_TYPE ------------------------ .. versionadded:: 3.17 Specifies the configuration to use by default in a ``build.ninja`` file in the :generator:`Ninja Multi-Config` generator. If this variable is specified, ``build.ninja`` uses build rules from ``build-.ninja`` by default. All custom commands are executed with this configuration. If the variable is not specified, the first item from :variable:`CMAKE_CONFIGURATION_TYPES` is used instead. The value of this variable must be one of the items from :variable:`CMAKE_CONFIGURATION_TYPES`.