Cannot find module 'mongodb'

gistfile1.txt

error:   Error running command deploy
error:   Nodejitsu Error (500): Internal Server Error
error:
error:   There was an error while attempting to start your application.
error:   Error spawning drone
error:   Script prematurely exited
error:
error:   This type of error is usually a user error.
error:   Error output from your application:
error:
error:   module.js:340
error:       throw err;
error:             ^
error:   Error: Cannot find module 'mongodb'
error:       at Function.Module._resolveFilename (module.js:338:15)
error:       at Function.Module._load (module.js:280:25)
error:       at Module.require (module.js:362:17)
error:       at require (module.js:378:17)
error:       at Object.<anonymous> (/opt/haibu/apps/xxxx/package/main.js:1:75)
error:       at Module._compile (module.js:449:26)
error:       at Object.Module._extensions..js (module.js:467:10)
error:       at Module.load (module.js:356:32)
error:       at Function.Module._load (module.js:312:12)
error:       at Function.Module.runMain (module.js:492:10)