NoSQL Meets Bitcoin and Brings Down Two Exchanges: The Story of Flexcoin and Poloniex Flexcoin was a Bitcoin exchange that shut down on March 3rd, 2014, when someone allegedly hacked in and made off with 896 BTC in the hot wallet. Because the half-million dollar heist from the hot wallet was too large for the company to bear, it folded. I'll resist the urge to ask why they did not have deposit ins