Grunt watching less and coffee Compiles individual files

Gruntfile.js

var path = require('path');

module.exports = function(grunt) {

  // Project configuration.
  grunt.initConfig({
    pkg: grunt.file.readJSON('package.json'),
    coffee: {
      all: {
        files: [{
            src: ["lib/**/*.coffee"],
            expand: true,
            rename: function(destBase, destPath) {
              return destPath.replace(".coffee", ".js");
            }
          }
        ]
      },
      changed: {
        files: {}
      }
    },
    less: {
      all: {
        files: [{
            src: ["styles/**/*.less"],
            expand: true,
            rename: function(destBase, destPath) {
              return destPath.replace(".less", ".css");
            }
          }
        ]
      },
      changed: {
        files: {}
      }
    },
    regarde: {
      coffee: {
        files: ["lib/**/*.coffee"],
        tasks: ["coffee:changed"],
        options: {
          nospawn: true
        }
      },
      less: {
        files: ["styles/**/*.less"],
        tasks: ["less:changed"],
        options: {
          nospawn: true
        }
      }
    }

  });


  grunt.event.on('regarde:file', function onFileChange(change, type, filepath, other){
      var filesConfig = {},
        extension = path.extname(filepath).split('.'),
        fileType = extension[extension.length - 1], targetFile;
      if(fileType === 'coffee'){
        targetFile = filepath.replace(".coffee",".js");
      } 
      if(fileType === 'less'){
        targetFile = filepath.replace(".less",".css");
      }
      filesConfig[targetFile] = filepath;
      console.log(arguments);
      grunt.config([fileType,'changed'], {
        files: filesConfig
      });
  });

  // Load the plugin that provides the "uglify" task.
  grunt.loadNpmTasks('grunt-contrib-coffee');
  grunt.loadNpmTasks('grunt-contrib-less');
  grunt.loadNpmTasks('grunt-regarde');
};