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A simple build tool that uses Google Closure Compiler's Java API to watch files in IDE mode for faster type checking. In watch mode, it integrates error reporting into OS X Lion's notification system using node-terminal-notifier. It also contains special minification rules for WebGL code including GLSL minification (run gccjs -o in the example folder to see it in action).


--check (-c)          Run checks (some checks only work with --optimize)
--help (-h)           Displays this message
--no-warnings (-e)    Treat warnings as errors
--optimize (-o)       Optimize and minify (default just links to sources)
--project (-p) FILE   The project file (defaults to project.json)
--watch (-w)          Builds every time a file changes, implies --check

Project format (JSON)

  // Required
  "target": "compiled.js",
  "sources": ["foo.js", "bar.js"],

  // Optional
  "externs": ["jquery.externs.js"],
  "before": [""],
  "after": [""],
  "defines": { "LOGGING": true },
  "wrapper": "(function() {%output%})();"

Example usage

$ sudo npm install -g gccjs
$ echo '/** @type {number} */ var foo = false;' > foo.js
$ echo '{ "target": "out.js", "sources": ["foo.js"] }' > project.json
$ gccjs --watch
Warning: initializing variable (line 1 of foo.js)
found   : boolean
required: number
Success (4.5 seconds)