title: Is it possible to make Heroku install the mongodb NPM package with the C++ BSON parser?
body: <p>Locally, I can run <code>npm install --mongodb:native</code> to get npm to compile and install the C++ BSON parser, but I can't replicate the same action on Heroku.</p>
  
  <p>I tried adding a pre-install command <code>npm install mongodb --mongodb:native</code> to <code>package.json</code> but <code>npm</code> isn't actually available on the path in the Heroku environment.</p>
  
  <p>Looking at <a href="https://github.com/christkv/node-mongodb-native/blob/master/install.js" rel="noreferrer">the source</a> for the mongodb package, it looks like it's looking for an environment variable (created by npm based on the command line argument I guess). Maybe there's a way of injecting that into the Heroku build environment?  </p>
  
  <p>BSON (de)serialisation is becoming a big CPU + memory hog for my app, and the C++ parser helps alleviate this.</p>