Not to detract from an interesting post, but the last point about programming languages is confusing, and seems to give little information.

Use expressive, untyped Ruby or inexpressive, strongly typed Go? Or SBCL ?

Most people would put Ruby and Go on pretty opposite sides of the spectrum.

Maybe you prototyped in SBCL when you needed extreme flexibility/iteration speed at first, and then switched to Go when maintenance became more important? That's a fairly common evolution at big companies.