Gulp is used for compiling, minifying, and concatenating SASS and Javascript.
To compile SASS, use gulp sass. This will search the ./public/css/src directory recursively for SASS files, compile, minify, and concatenate them, then place a single CSS file called 'main.min.css' in the ./public/css/dist directory. To compile SASS, but skip the minification and concatenation process, use gulp sass -d. This will produce one compiled CSS file in the ./public/css/dist directory for each source SASS file. SASS files prepended with an underscore will be ignored.
To compile Javascript, use gulp js. This will search the ./public/js/src directory non-recursively for Javascript files, browserify, concatenate, and minify them, then place a single Javascript file called 'main.min.js' in the ./public/js/dist directory. To browserify each source file as an individual bundle and skip the minification process, use gulp js -d. This will produce one browserified Javascript file in the ./public/js/dist directory for each source Javascript file.