text: 
  "use strict";
  
  var scrypt = require("scrypt");
  
  module.exports = function(options) {
  
    options = options || {};
    
    var maxTime = options.maxTime || 0.2;
  
    var params = scrypt.paramsSync(maxTime);
  
    var hash = function(str, callback) {
      scrypt.kdf(str, params, callback);
    };
  
    var compare = function(str, hash, callback) {
      scrypt.verifyKdf(hash, str, callback);
    };
  
    return {
      hash:    hash,
      compare: compare
    };
  
  }
  