Jesse Powell knew Mt. Gox was not long for this world more than two years before the once-dominant bitcoin exchange went bankrupt in February.

In June 2011, Powell took a last-minute flight to Tokyo to help Mt. Gox recover from a hacking attack. He ran the day-to-day business, drafting press releases, hiring and training staff, while Chief Executive Officer Mark Karpeles focused on reviving the service. A month after the trip, Powell founded a competitor — Kraken. It is in talks to offer services in Japan, he said in an interview, declining to give a date.

"It was clear after that hack at Mt. Gox, when they were down for like a week, that the exchange is really the most critical piece of the ecosystem," said Powell, 33, who started dealing with digital currencies more than a decade ago when he set up an online store for virtual swords and armor. "I wanted there to be another one to take its place, if Mt. Gox failed."