If you got an error on dumping assets
$ php app/console assetic:dump
[Assetic\Exception\FilterException] An error occurred while running: '/usr/sbin/node' '/tmp/assetic_lessl9esGS
Check anf fix all paths for nodejs and less, or just try this configuration
assetic: debug: "%kernel.debug%" use_controller: false bundles: [ ] #java: /usr/bin/java filters: less: bin: /usr/local/bin/lessc node: /usr/bin/nodejs node_paths: ["/usr/local/lib/node_modules"] apply_to: "\.less$"