For developers that are creating libraries and modules, it is generally preferable to make your code available to as broad of range of users as possible. There are several different module formats in JavaScript (a module is an encapsulation of code that draws on other modules). Picking one format is often mutually exclusive to the other formats. However, in this post I want to demonstrate how you can write JavaScript modules that can be used with multiple module loaders using some simple boilerplate. Of course not all the module loaders necessarily make sense for all modules. If you are writing a module that relies on the Node file system API, it only needs it to work with the NodeJS/CommonJS module format. Likewise, a DOM-based module wouldn’t need to run on Node.

Here we’ll deal with the actual module format, the mechanism of specifying dependencies and exporting or returning functions from the module that can be used by the users. This does not deal with the normalization of the actual APIs of the underlying system, although you might want to take a look at promised-io if you would like normalization of IO interaction across the browser, Node, and Rhino/Narwhal.

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