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Pure minimalistic CommonJS builder

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Pure CommonJS Modules builder.


  • Minimal destination overhead (almost as small as concatenated file).
  • Resolves all the paths on build stage to static number identifiers (so saves space and execution time used for storing and resolving string paths, but should be used only for projects with static require('./some/module') calls and would fail on others (same restriction applicable for r.js (Simplified CommonJS wrapper) and most projects already match this).
  • Ability to export module.exports from top module in UMD style (useful for building libs).
  • Allows to use through-stream(s) for pre-transformations.
  • Supports modules installed as npm dependencies in node_modules hierarchy.
  • Does not corrupt require('systemModule') calls, transforms only local ones.

Console usage


npm install -g pure-cjs

Command-line options:

-h, --help             output usage information
-V, --version          output the version number
-i, --input <file>     input file (required)
-o, --output <file>    output file (defaults to <input>.out.js)
-m, --map <file>       file to store source map to (optional, defaults to <output>.map)
-c, --comments         preserve comments in output
-e, --exports <id>     top module exports destination (optional)
-x, --extension <ext>  default extension for requires (defaults to "js")
-d, --module-dir <dir> modules directory name to look in (defaults to "node_modules")

Usage from Node.js

var cjs = require('pure-cjs');

cjs.transform(options).then(function (result) {
    // handle successful result
}, function (err) {
    // handle error

Result object

  • code: String — generated source code.
  • map: Object — source map object.
  • options: Object — options object with resolved defaults and paths.

Usage from Grunt

Check out grunt-pure-cjs to use builder as Grunt plugin.