stylus-variable-loader
This is an experimental thing, be careful.
Usage
//vars.styl$size = 12px;$padding = 10px 12px;$color = #FFF;$expr-color = $color, 0.5);$button = {$color: white,$background: black,$font-size: 1.2em}
//vars.js;console;'$size': '12px''$padding': '10px 12px''$color': '#FFF''$expr-color': 'rgba(255, 255, 255, 0.5)''$button':'$color': 'white''$background': 'black''$font-size': '1.2em'