Fibers, sometimes called coroutines, are a powerful tool which expose an API to jump between multiple call stacks from within a single thread. This can be useful to make code written for a synchronous library play nicely in an asynchronous environment. Note: node-fibers uses node-gyp for building. To manually invoke the build process, you can use node-gyp rebuild. This will put the compiled extension in build/Release/fibers.node. However, when you do require('fibers'), it will expect the module to be in, for example, bin/linux-x64-v8-3.11/fibers.node. You can manually put the module here every time you build, or you can use the included build script. Either npm install or node build -f will do this for you. If you are going to be hacking on node-fibers, it may be worthwhile to first do node-gyp configure and then for subsequent rebuilds you can just do node-gyp build which will be faster than a full npm install or node-gyp rebuild.