When I run brunch build I’m getting a number of warnings like so

warn: js/admin/app-admin.js compiled, but not written. Check your javascripts.joinTo config

Any idea what’s causing this here is my config (my project is using admin and public to load different js and css)
exports.config = {
// See Brunch - ultra-fast HTML5 build tool for docs.
files: {
javascripts: {
joinTo: {
// public js
‘js/app.js’: /^(assets/js/public)/,
‘js/countdown.js’: /^(assets/js/public)/,
‘js/jquery.steps.min.js’: /^(assets/js/public)/,
‘js/jquery-3.1.1.min.js’: /^(assets/js/public)/,
‘js/flickity.min.js’: /^(assets/js/public)/,
‘js/parallax.js’: /^(assets/js/public)/,
‘js/scripts.js’: /^(assets/js/public)/,
‘js/smooth-scroll.min.js’: /^(assets/js/public)/,
‘js/typed.min.js’: /^(assets/js/public)/,
‘js/ytplayer.min.js’: /^(assets/js/public)/,

        // admin js
        'js/app-admin.js': /^(assets\/js\/admin)/ ,
        'js/jquery-1.11.2.min.js': /^(assets\/js\/admin)/,
        'js/jquery-migrate-1.2.1.min.js': /^(assets\/js\/admin)/,
        'js/bootstrap.js': /^(assets\/js\/admin)/,
        'js/jquery.autosize.js': /^(assets\/js\/admin)/,
        'js/jquery.App2.js': /^(assets\/js\/admin)/,
        'js/jquery.AppNavigation2.js': /^(assets\/js\/admin)/,
        'js/jquery.editirmd.js': /^(assets\/js\/admin)/,
        'js/lib/flowchart.min.js': /^(assets\/js\/admin)/,
        'js/lib/jquery.flowchart.min.js': /^(assets\/js\/admin)/,
        'js/lib/marked.min.js': /^(assets\/css\/admin)/,
        'js/lib/prettify.min.js': /^(assets\/js\/admin)/,
        'js/lib/raphael.min.js': /^(assets\/js\/admin)/,
        'js/lib/sequence-diagram.min.js': /^(assets\/js\/admin)/,
        'js/lib/underscore.min.js': /^(assets\/js\/admin)/,
      }

      // To use a separate vendor.js bundle, specify two files path
      // http://brunch.io/docs/config#-files-
      // joinTo: {
      //   "js/app.js": /^js/,
      //   "js/vendor.js": /^(?!js)/
      // }
      //
      // To change the order of concatenation of files, explicitly mention here
      // order: {
      //   before: [
      //     "vendor/js/jquery-2.1.1.js",
      //     "vendor/js/bootstrap.min.js"
      //   ]
      // }
    },
    stylesheets: {
      joinTo: {
        // Public css
        'css/bootstrap.css': /^(assets\/css\/public)/,
        'css/stack-interface.css': /^(assets\/css\/public)/,
        'css/socicon.css': /^(assets\/css\/public)/,
        'css/flickity.css': /^(assets\/css\/public)/,
        'css/iconsmind.css': /^(assets\/css\/public)/,
        'css/query.steps.css': /^(assets\/css\/public)/,
        'css/theme.css': /^(assets\/css\/public)/,
        'css/custom.css': /^(assets\/css\/public)/,
        'css/lightbox.min.css': /^(assets\/css\/public)/,

        // Admin css
        'css/bootstrap2.css': /^(assets\/css\/admin)/,
        'css/materialadmin.css': /^(assets\/css\/admin)/,
        'css/font-awesome.css': /^(assets\/css\/admin)/,
        'css/material-design-iconic-font.css': /^(assets\/css\/admin)/,
        'css/editormd.css': /^(assets\/css\/admin)/,
      }
    },
    templates: {
      joinTo: "js/app.js",
    }
  },

  conventions: {
    // This option sets where we should place non-css and non-js assets in.
    // By default, we set this to "/assets/static". Files in this directory
    // will be copied to `paths.public`, which is "priv/static" by default.
    assets: /^(static)/
  },

  // Phoenix paths configuration
  paths: {
    // Dependencies and current project directories to watch
    watched: ["static", "css", "js", "vendor"],
    // Where to compile files to
    public: "../priv/static"
  },

  // Configure your plugins
  plugins: {
    babel: {
      // Do not use ES6 compiler in vendor code
      //ignore: [/vendor/]


      ignore: [
        /vendor/,
        /assets\/css\/public\/vendor/,
        /assets\/css\/admin\/vendor/
      ]
    }
  },

  modules: {
    autoRequire: {
      "js/app.js": ["js/app"],
    }
  },

  npm: {
    enabled: true
  }
};