The OpenLayers build tool supports several different forms of compressing your javascript code, and a method of describing build profiles to create customized OpenLayers builds with only the components you need. When building a file, you can choose to build with several different compression options to the Python-based build.py script. The following is an example script: python build.py -c closure full OpenLayers-closure.js This script selects the 'closure' compression mechanism, uses a config file called 'full.cfg', and writes the output to OpenLayers-closure.js. The options available for compression are: * closure This requires you to have a closure-compiler.jar in your tools directory. You can do this by fetching the compiler from: http://closure-compiler.googlecode.com/files/compiler-latest.zip Then unzipping that file, and placing compiler.jar into tools and renaming it closure-compiler.jar. * closure_ws This uses the closure compiler webservice. This will only work for files source Javascript files which are under 1MB. (Note that the default OpenLayers full build is not under 1MB.) * jsmin jsmin is the default compiler, and uses the Python-based jsmin script to compress the Javascript. * minimize This is a simple whitespace removing Python script, designed to fill in when other tools are unavailable. * none None will leave the Javascript uncompressed.