Can't seem to get this to work with Browserify command line

[notacouch]

I'm using browserify via command line and should be able to just run browserify -t bulkify in.js > bundle.js, but I always get the following error in browser:

TypeError: fs.readdirSync is not a function

It seems to be related to the changes here: https://github.com/therebelrobot/countryjs/issues/57

so I rolled back to a previous commit, and I still get the above error.

Please advise.