Those interested in building a Bitcoin exchange should look no further than this chunk of source code posted by a “Russian leaker” called nanashi_. It alleges to contain the 1,700-line source code for Mt. Gox’s electronic exchange.
The code describes the Bitcoin class for Mt. Gox and the various methods for transmitting and receiving BTC. Hacker News believes that CEO Mark Karpeles AKA MagicaTux wrote some of the code.
Here is a private mirror of the code but you can also read it here. The hackers also claim to have a 20GB data dump of customer data along with passport scans and a list of contact information for Mt. Gox employees. The full IRC exchange with the leaker is here.