Some time ago, I was in a meeting with a development team at a client site when the vice president of IT made an unscheduled visit to say hello and meet new team members. Apropos of nothing, he announced, “I like modularity! Software that can be assembled like Lego bricks.” Composable software is, indeed, an attractive vision—a vision shared by Brad Cox, an early and influential exponent of the Object-Oriented Programming (OOP) movement. OOP offered Cox a glimpse at the future potential for composable software architectures that would usher in “A software industrial revolution based on reusable and interchangeable parts…” that would, he promised, “…alter the software universe.100F”