Infusion's Node.js module ships with requireStub.js, which is currently used in the GPII universal repository to enable our tests to run in both Node.js and in the browser. Its purpose is primarily to provide a stubbed version of Node.js's require() function, mapping between module names and global namespace names (e.g. "infusion" -> fluid).
Colin suggested that it would be simpler to just use the following boilerplate when accessing modules that are designed to work and be tested in both the browser and Node:
var globalName = globalName || require("moduleName");
Using this idiom avoids the need for requireStub.js, so it can be removed from Infusion.