This is how to cache and enqueue (eg. bootstrap):

this is how to compile the bootstrap 3 less files, including caching, so the file is only recompiled when a less file has changed:


function my_enqueue_scripts(){
$less_files = array( get_stylesheet_directory() . '/less/bootstrap.less' => '/mysite/' );
$options = array( 'cache_dir' => get_stylesheet_directory() . '/lesscache' );
$css_file_name = Less_Cache::Get( $less_files, $options );
wp_enqueue_style( 'bootstrap', get_stylesheet_directory_uri() . '/lesscache/'.$css_file_name);
}
// Uncomment this to add a additional scripts
add_action( 'wp_enqueue_scripts', 'my_enqueue_scripts' );


if you want to use bootstrap variables in your own less file (which you probably do), simply stick this on top

@import “/less/bootstrap.less”;

and process your own less file instead of bootstrap.less.

you dont need anything else, just install the plugin and above code.

and check here to see detailled explanation:
https://github.com/oyejorge/less.php

greets and thanks for this great plugin! less just became much more… useful. (after the trusty wp-less plugin failed compiling bootstrap 3)

https://www.ads-software.com/plugins/lessphp/