Heroku Cannot find module 'lodash/object/assign' - node.js

Question

I'm having issues deploying to Heroku. Got it running locally after i had the same error by simply rm -f node_modules and then reinstalling them with npm install. But when i deploy to heroku the error keeps occurring. Even went in with bash to perform the same steps.
I then used npm shrinkwrap and noticed aws-sdk has a dependency on lodash vs 3.5.0 <3.6.0. So i set the lodash version in my package.json accordingly.
It all still runs locally but keeps crashing on heroku.
Node v5.0.0
NPM v3.3.6
"dependencies": {
"aws-sdk": "^2.6.6",
"bluebird": "^3.4.6",
"body-parser": "^1.15.2",
"express": "^4.14.0",
"goosepage": "0.0.1",
"lodash": "^3.5.0"
}
Additional heroku log
Error: Cannot find module 'lodash/object/assign'
Function.Module._resolveFilename (module.js:337:15)
Function.Module._load (module.js:287:25)
Module.require (module.js:366:17)
require (module.js:385:17)
Object.<anonymous> (/app/node_modules/xmlbuilder/lib/index.js:5:12)
Object.<anonymous> (/app/node_modules/xmlbuilder/lib/index.js:14:4)
Module._compile (module.js:425:26)
Object.Module._extensions..js (module.js:432:10)
Module.load (module.js:356:32)
Function.Module._load (module.js:311:12)
Module.require (module.js:366:17)
require (module.js:385:17)
Object.<anonymous> (/app/node_modules/aws-sdk/lib/xml/builder.js:2:15)
Module._compile (module.js:425:26)
Object.Module._extensions..js (module.js:432:10)
Module.load (module.js:356:32)

Answer 1

Turns out Heroku had a Buildpack that was caching node_modules. Turning off caching didnt help so i had to use the heroku plugin to clear the cached which worked.
https://github.com/heroku/heroku-repo
heroku repo:purge_cache -a appname
The following allegedly should also work incase the above doesn't
heroku config:set NODE_MODULES_TRUE=false