So: suppose you wanted to build a scaled-down version of a real application that (a) illustrated some software design ideas in the concurrency/fault tolerance/distributed computing/networking space that (b) you could explain in 50 minutes to people moderately familiar with the programming language you're using but _not_ familiar with the problem domain or design idea. (See the chapters of https://third-bit.com/sdxjs/ and https://third-bit.com/sdxpy/ for scale.) What would you pick and why? #sdx