Braintree has an opinionated approach to software development. One thing we feel particularly strongly about is pair programming. We pair for almost everything. Often when discussing pair programming, people focus on the effect of pairing on code quality and developer productivity. The argument goes: a pair costs twice as much as a single developer, but if they deliver code in X% of the time, with Y% fewer bugs and Z% less technical debt, then depending on your measurement of X, Y and Z, pairing might make sense.