Automated javascript combination and minification
Python Shell
Switch branches/tags
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.


Merge and Simplify Scripts (MASS)

Inspired by SASS, MASS is an automated tool for managing javascript files in a web projects.


  • easy method to combine multiple files into single asset request
  • automated minification/optimization
  • extending javascript to allow import other scripts


  • Mac OS X (currently using fsevents to track file changes. will later add support for Linux and Windows)

Python Packages Used


MASS can be installed via pip:

pip install mass

To install MASS manually, clone the repo and install using

python install

MASS comes with the necessary python packages via virutalenv by default.

Before installing MASS, users can enable virtualenv by navigating to the repository and sourcing the virtual environment.

cd path/to/MASS
source env/bin/activate

Source Files

Source files use the extension '.xjs', which tentatively signifies extended javascript. These files are used to define javascript files which will be included in a "compiled" version that is output by MASS.

Including Files

Inside 'extended' javascript files, you can import other scripts. All javascript files listed in the source file will be combined, minified and output to a javascript file with the same name as the original xjs file. Paths to imported javascript files should be relative to the directory of the xjs file they are imported into.

The example below specifies two javascript files and will be output to the file foo.min.js:

// foo.xjs
// import "foo.js"
// import "plugins/jquery.jnotify.js"

Require commands can be used to ensure that a file has been already been imported, and will import the script if they have not.

// foo.xjs
// import "foo.js"
// import "bar.js"

// foo.js
// require "bar.js" 

In the above example, bar.js will not be re-imported since foo.xjs has already imported it.

MASS also supports 'inline' javascript

// bar.js
// import "foo.js"

// now some javascript 
    // jquery is ready

// another import!
// import "plugins/jquery.jnotify.js"

CLI Arguments

###Basic Commands

Mass has two basic CLI commands, watch and compile. watch begins monitoring the specified directory and will compile files as they are edited while compile will simply minify and combine files located in the specified directory.

mass watch -s path/to/source

mass compile -s path/to/source

###Defining Destination Directory

By default, MASS saves the compiled js files in the same directory as the source files. The -d argument can be used to specify a different output directory.

mass watch -d path/to/output

###Defining Source Directory

If a source directory is not specified, MASS uses the current directory by default. The -s argument can be used to specify the directory for MASS to discover files.

mass watch -s path/to/source -d path/to/output