global.conf

Warning

This new configuration mechanism is an experimental feature subject to breaking changes in future releases.

The global.conf file is located in the Conan user home directory.

Global configuration

core:required_conan_version = "expression" allows defining a version expression like “>=1.30”. Conan will raise an error if its current version does not satisfy the condition
core.package_id:msvc_visual_incompatible allows opting-out the fallback from the new msvc compiler to the Visual Studio compiler existing binaries

Tools configurations

Tools and user configurations allows them to be defined both in the global.conf file and in profile files. Profile values will have priority over globally defined ones in global.conf, and can be defined as:

[settings]
...

[conf]
tools.microsoft.msbuild:verbosity=Diagnostic
tools.microsoft.msbuild:max_cpu_count=20
tools.microsoft.msbuild:vs_version = 16
tools.build:processes=10
tools.ninja:jobs=30
tools.gnu.make:jobs=40

Existing configurations:

tools.microsoft.msbuild:verbosity allows defining a value from "Quiet", "Minimal", "Normal", "Detailed", "Diagnostic" for build using the MSBuild system, it could be with the tools.microsoft.MSBuild or with the tools.cmake.CMake helpers.
tools.microsoft.msbuild:max_cpu_count argument for the /m (/maxCpuCount) when running MSBuild standalone or via CMake (overrides the general tools.build:processes).
tools.microsoft.msbuild:vs_version defines the compiler version when using using the new msvc compiler.
tools.build:processes: number of processes to use for every build-helper.
tools.ninja:jobs argument for the --jobs parameter when running Ninja generator via CMake or Meson. (overrides the general tools.build:processes).
tools.gnu.make:jobs: argument for the --jobs parameter when running make (overrides the general tools.build:processes).

To list all possible configurations available, run conan config list.

Configuration from build_requires

From Conan 1.37, it is possible to define configuration in packages that are build_requires. For example, assuming there is a package that bundles the AndroidNDK, it could define the location of such NDK to the tools.android:ndk_path configuration as:

import os
from conans import ConanFile

class Pkg(ConanFile):
    name = "android_ndk"

    def package_info(self):
        self.conf_info["tools.android:ndk_path"] = os.path.join(self.package_folder, "ndk")

Note that this only propagates from the immediate, direct build_requires of a recipe.