browserify | node hasher.js './bundle.%s.js'

hasher.js

var fs = require('fs');
var util = require("util");
var crypto = require("crypto");
var shasum = crypto.createHash('sha1');
var tempName = './.temp' + Math.random();
var temp = fs.createWriteStream(tempName);
process.stdin.pipe(shasum);
process.stdin.pipe(temp);
process.stdin.on('end', function() {
  var name = util.format(process.argv[2],shasum.digest('hex').slice(0,7));
  fs.createReadStream(tempName).pipe(fs.createWriteStream(name)).on('end', function (){
    fs.unlink(temp, function (e) {
      if (e) {
        process.exit(1);
      }
      process.exit();
    });
  })
});