Basic Grunt/Sass Setup

Gruntfile.js

module.exports = function(grunt) {
    // Project configuration.
    grunt.initConfig({
        pkg: grunt.file.readJSON('package.json'),

        uglify: {
            build: {
                src: 'js/scripts.js',
                dest: 'js/scripts.min.js'
            }
        },

        sass: {
            dev: {
                src: ['sass/**/*.scss'],
                dest: 'style.css',
            },
        },

        watch: {

            php: {
                files: [ '**/*.php' ],
                options: {
                    livereload: true,
                }
            },

            sass: {
                //We watch and compile sass files as normal but don't live reload here
                files: ['sass/**/*.scss'],
                tasks: ['sass'],
                options: {
                    livereload: true,
                }
            },

            options: {
                livereload: {
                    options: {
                        livereload: true
                    }
                }
            }
        },
    });

    grunt.loadNpmTasks('grunt-contrib-uglify');
    grunt.loadNpmTasks('grunt-contrib-sass');
    grunt.loadNpmTasks('grunt-contrib-watch');

    // Default task(s).
    grunt.registerTask('default', ['watch']);
};

package.json

{
  "name": "basic-grunt-sass-setup",
  "version": "0.1.0",
  "devDependencies": {
    "grunt": "^0.4.5",
    "grunt-contrib-sass": "^0.7.3",
    "grunt-contrib-uglify": "^0.4.0",
    "grunt-contrib-watch": "^0.6.1"
  }
}