[pavlov]

I was surprised to learn that PayPal has 16,000 employees! If I'd had to guess, I would have said something around 1000.

I guess there is a lot of manual work involved in handling all those transactions and fraud attempts.

[thephyber]

I'd wager that much of their workforce is engineering and integration support, in addition to the redundancy they purchased by buying companies like BrainTree.

Additionally, PayPal owns a massive amount of legacy code and APIs. There are plenty of con talks where PayPal describes how they were mired down in bureaucracy when updating a single line of code in Java (JSP) but managed to flip that overhead on its head by running a NodeJS stack on top of the JSP stack (and in some places replacing it).