gulp - Gulpfile relative path to root -

i want approach deploy folder gulpfile, placed gulpfile in source folder stays tidy. current folder structure:

deploy ├── js ├── css ├── img └── index.php source ├── node_modules ├── base ├── structure └── gulpfile.js 

structure above part of full tree

part of gulpfile.js:

var path = {     js: {         src: [             './source/_base/**/js/*.js',             './source/_structure/**/js/*.js'         ],         deploy: [             '../deploy/js/'         ]     }, // more below line 

the gulp task:

gulp.task('process-js', function(){     gulp.src(path.js.src)     .pipe(plumber())     .pipe(jshint())     .pipe(jshint.reporter(stylish))     .pipe(concat('main.min.js'))     .pipe(uglify())     .pipe(plumber.stop())     .pipe(gulp.dest(path.js.deploy)); }); 

when execute gulp task (which uses deploy path) error:
:error: invalid output folder @ gulp.dest

question:
how can use gulpfile relative path place files in parent of root folder.

i've found solution, - of course - not possible parse array destination.