gulpconfig.json

{
    "watch": [
        {
            "files"    : "source/less/**/*.less",
            "build" : { "less" : "default" }
        },
        {
            "files"   : "source/js/scripts.js",
            "build" : { "js" : "default" }
        },
        {
            "files"   : [
                "source/js/vendor/**/*.js",
                "source/js/vendors.js"
            ],
            "build" : { "js" : "vendors" }
        },
        {
            "files"   : "source/js/customizer.js",
            "build" : { "js" : "customizer" }
        },
        {
            "files"    : "source/admin/less/**/*.less",
            "build" : { "less" : "admin" }
        },
        {
            "files"    : "source/admin/js/**/*.js",
            "build" : { "js" : "admin" }
        }
    ],
    "build": {
        "less": {
            "default": {
                "source/less/font-awesome.less": [
                    "css"
                ],
                "source/less/style.less": [
                    "css"
                ],
                "source/less/color-blue.less": [
                    "css"
                ],
                "source/less/color-green.less": [
                    "css"
                ],
                "source/less/color-orange.less": [
                    "css"
                ],
                "source/less/color-purple.less": [
                    "css"
                ],
                "source/less/color-yellow.less": [
                    "css"
                ]
            },
            "admin": {
                "source/admin/less/pine-customize-control-color-scheme.less": [
                    "admin/css"
                ],
                "source/admin/less/pine-customize-control-layout.less": [
                    "admin/css"
                ],
                "source/admin/less/pine-customize-control-social-buttons.less": [
                    "admin/css"
                ],
                "source/admin/less/pine-editor.less": [
                    "admin/css"
                ],
                "source/admin/less/pine-admin-page.less": [
                    "admin/css"
                ]
            }
        },
        "js": {
            "default": {
                "source/js/scripts.js": [
                    "js"
                ]
            },
            "vendors": {
                "source/js/vendors.js": [
                    "js"
                ]
            },
            "customizer": {
                "source/js/customizer.js": [
                    "js"
                ]
            },
            "admin": {
                "source/admin/js/pine-customize-control-color-scheme.js": [
                    "admin/js"
                ],
                "source/admin/js/pine-customize-control-layout.js": [
                    "admin/js"
                ],
                "source/admin/js/pine-customize-control-social-buttons.js": [
                    "admin/js"
                ],
                "source/admin/js/pine-less.js": [
                    "admin/js"
                ],
                "source/admin/js/pine-notifications.js": [
                  "admin/js"
                ]
            }
        }
    }
}