text: var Transaction = require('ethereumjs-tx');
  var util = require("ethereumjs-util");
  var secp256k1 = util.secp256k1;
  
  // Simple unencrypted signer, not to be used in the browser
  
  var SimpleSigner = function(keypair) {
    this.keypair = keypair;
  }
  
  SimpleSigner.prototype.getAddress = function() {
    return this.keypair.address;
  }
  
  SimpleSigner.prototype.signRawTx = function(rawTx, callback) {
    var rawTx = util.stripHexPrefix(rawTx);
    var txCopy = new Transaction(new Buffer(rawTx, 'hex'));
    txCopy.sign(new Buffer(util.stripHexPrefix(this.keypair.privateKey), 'hex'));
    callback(null, txCopy.serialize().toString('hex'));
  }
  
  
  module.exports = SimpleSigner;
  