                 ext: '.css'
                 dest: '<%= app.build.path %>/styles/'
         }
-
+        # some cool commands
         shell: {
+            # start chrome driver
             webdriver:
                 command: 'webdriver-manager start'
                 keepalive: yes
-                options:
-                    stdout: yes
+                options: stdout: yes
+            # mark the current build with a stamp in `current`/.build file
+            mark: command: 'echo <%= timestamp %> > <%= app.build.current %>/.build'
         }
 
         karma: {

                current: 'current'
        }

        # grunt-contrib-watch: watch our files for changes
        watch: {


        copy: {
            # copy our latest build to
            # the corresponding current directory
            current:
                files: [
                    {
                        expand: yes
                        nonull: yes
                        cwd: '<%= app.build.path %>'
                        src: ['**/*.js', '**/*.css']
                        dest: '<%= app.build.current %>/'
                    }
                ]

            build:
                files: [
                    {
                        expand: yes
                        nonull: yes
                        cwd: '<%= app.build.dir%>/<%= timestamp %>'
                        src: ['**/*.js', '**/*.css']
                        dest: '<%= app.build.current %>/'
                    }
