This is the new networking layer for Node. Its purpose is to abstract IOCP on windows and libev on Unix systems. We intend to eventually contain all platform differences in this library. http://nodejs.org/ = Build Instructions For GCC (including MinGW) there are two methods building: via normal makefiles or via GYP. GYP is a meta-build system which can generate MSVS, Makefile, and XCode backends. It is best used for integration into other projects. The old (more stable) system is using Makefiles. To build via Makefile simply execute: make To build with Visual Studio run the vcbuilds.bat file which will checkout the GYP code into build/gyp and generate the uv.sln and related files. Windows users can also build from cmd-line using msbuild. This is done by running vcbuild.bat from Visual Studio command prompt. To have GYP generate build script for another system you will need to checkout GYP into the project tree manually: svn co http://gyp.googlecode.com/svn/trunk build/gyp Unix users run ./gyp_uv -f make make Macintosh users run ./gyp_uv -f xcode xcodebuild -project uv.xcodeproj -configuration Release -target All = Supported Platforms Microsoft Windows operating systems since Windows XP SP2. It can be built with either Visual Studio or MinGW. Linux 2.6 using the GCC toolchain. MacOS using the GCC or XCode toolchain. Solaris 121 and later using GCC toolchain.