After installation, npm will automatically execute this module, which downloads and installs Visual C++ Build Tools, provided free of charge by Microsoft. These tools are required to compile popular native modules. If not already installed, it will also install Python 2.7, configuring your machine and npm appropriately. Both installations are conflict-free, meaning that they do not mess with existing installations of Visual Studio, C++ Build Tools, or Python. If you see anything that indicates otherwise, please file a bug.