Braintree, a payments platform for developers and retailers, is moving into larger facilities in both Chicago and Silicon Valley ahead of significant planned growth. The company’s 60 employees are currently spread across offices in Chicago and Silicon Valley and the company is expanding in both locations to the tune of a approximately 40 new hires in 2012.

Used by over 2,000 customers, including Uber, HotelTonight, and Fab, Braintree processes $4 billion in payments annually, a number which CEO Bill Ready expects to increase to $5 billion in the near future. Of that, almost 25 percent is processed through mobile devices. Previously limited to the US, Braintree expanded its payments solution to the United Kingdom, the European Union, Australia, and Canada on June 5.

“We look for the top 1 percent kind of developers for our team. Everyone says that, but not everyone does it. We really have to, because our product isn’t for consumers. Our product is source code. It’s used by engineers at some of the best tech companies in the world,” Ready says. “We’ve been able to find those guys here in Chicago, but we need to hire more. And there’s no place that has more of those [types of engineers] than Silicon Valley.”

Ready is right about the amount of talent floating around Silicon Valley, but Braintree is going to face one huge problem: Despite having offices in the Valley, the company isn’t based in the Valley. A fine distinction, but one that can mean the difference between one of approximately one billion (note: not an actual statistic) other companies grabbing a “top 1 percent” developer and that developer choosing to work with Braintree.

Braintree counts a number of Silicon Valley’s high-profile startups as its customers, and it will become increasingly important for the company to be geographically close to those companies. Having offices in the Valley is a good start, but the difference between having an office in the Valley and calling the Valley home can’t be overstated.

While Ready says that Chicago has a growing tech scene, and that the city is a good fit for Braintree because that’s where the company was founded, at some point it becomes impractical to count the companies you work with as customers instead of neighbors.

[Disclosure: Accel Ventures, which has invested $34 million in Braintree, is an investor in PandoDaily by way of the Accel Seed Fund]