Calculus didn't exist in their time, so it couldn't be used by them. Moreover, much progress has been made in science, partly due to calculus. In fact, an aweso

Calculus didn't exist in their time, so it couldn't be used by them. Moreover, much progress has been made in science, partly due to calculus. In fact, an awesome scientist today is much more powerful than an awesome scientist back then. Can you show examples of practical progress made in computer science due to category theory? A bugfree web server, a secure web browser, an OS perhaps?