credentials.js

{ 
  "accessKeyId": "akid", 
  "secretAccessKey": "secret", 
  "region": "us-east-1" 
}

Gruntfile.js

'use strict';
 
module.exports = function(grunt) {
 
  // Project configuration.
  grunt.initConfig({
    concat: {
      dist: {
        src: ['main.js', 'ctrl1.js'], //source files goes here
        dest: 'build/lib.js'          //concatenated file goes here
      }
    },
    uglify: {
      options: {
        compress: {
          dead_code: true
        },
        wrap: true,
        sourceMap: true
      },
      dist: {
        src: '<%= concat.dist.dest %>',
        dest: 'build/lib.min.js',
      }
    },
    s3: {
      options: {
        region: 'us-east-1',
        endpoint: 's3.amazonaws.com',
        access: 'public-read',
        headers: { 'Cache-Control': 'max-age=60' },
        gzip: true,
        bucket: 'bucketname'
      },
      upload: [
        {
          src: 'path/to/builtlib.js',
          dest: 'path/in/s3/lib.js'
        }
      ]
    },
    cloudfront: 
      options: {
        credentials: grunt.file.readJSON('credentials.json'),
        region: 'us-east-1',
        distributionId: "YOUR_DISTRIBUTION_ID",
        listInvalidations: true
      },
      paths: [
        'url/of/cloudfront/lib.js'
      ]
    },
    hipchat_notifier: {
      options: {
        authToken: "", // your authtoken
        roomId: "" // Numeric Hipchat roomId
      },
      deployed: {
        message: 'Wow, deployed!',
        from: 'Wizard of Grunt',
        color: 'red'
      }
    }
  });
 
  grunt.loadNpmTasks('grunt-contrib-concat');
  grunt.loadNpmTasks('grunt-contrib-uglify');
  grunt.loadNpmTasks('grunt-s3');
  grunt.loadNpmTasks('grunt-cloudfront');
  grunt.loadNpmTasks('grunt-hipchat-notifier');
 
  //also, you could combine these steps, and have a task like:
  //grunt.registerTask('deploy', ['concat', 'uglify', 's3', 'cloudfront', 'hipchat_notifier']);
  grunt.registerTask('build', ['concat', 'uglify']);
  grunt.registerTask('deploy', ['s3', 'cloudfront', 'hipchat_notifier']);
};