Precompiling asset_path helper breaks

[secretfader]

Warning: [StylusEngine] /Users/nicholaswyoung/Code/platform/assets/css/includes/typography.styl:4
   1| @font-face {
   2|   font-family: 'Gibson Regular';
   3|   src: url(asset_path('Gibson-Regular.eot'));
 > 4|   src: url(asset_path('Gibson-Regular.eot') + '?#iefix') format('embedded-opentype'),
   5|         url(asset_path('Gibson-Regular.woff')) format('woff'), url(asset_path('Gibson-Regular.ttf')) format('truetype'),url(asset_path('Gibson-Regular.svg') + '#jvlkltqrnp') format('svg');
   6|   font-style: normal;
   7| }

Custom asset_path helper is not implemented

Extend your environment context with a custom method.

  environment.ContextClass.defineAssetPath(function (pathname, options) {
    // ... your code here ... 
  });