title: How do I include custom SASS functions during precompile?
body: <p>I've successfully extended some SASS functions with Ruby code (http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html#adding_custom_functions), and my extensions are loading correctly in development, but when I precompile my assets, the extensions are not loaded. The code lives in /app/models, but this is probably not the best place for it.</p>
  
  <p>I've tried explicitly requiring the file in a few different config files, but it continues to fail to load during precompile. This also seems like a poor approach.</p>
  
  <p>I know that the code is failing to load because the precompiled CSS leaves the function names in the CSS in plaintext. No errors are thrown.</p>
  
  <p>So: Where's the best place for a file like this to live, and how do I get SASS to load the file during precompile? </p>