> Setting it loose for the first time, knowing that any bug could literally throw away cash, was terrifying.
I am interested in projects that deal with real cash values as well and the unique concerns that come in. One design pattern I've read of is circuit breakers, like those used on the official exchanges [1] are typically implemented in HFT's; just stop trading if your total net loss that day is some order of magnitude higher than your typical expected losses.
I expected the market for bitcoins was saturated with market makers. Interesting that author was able to set up shop and make money.