Once you start trying to expose metrics, as I discuss in Designing for Transparency, rolling your own connection pool goes from a fun Computer Science 101 exercise to a tedious grind.
i.o.w. a lot of “comp sci” exercises probably really ARE given to undergrads but the point isn’t for them to create a fully baked solution so much as it is to illustrate how problems are devilishly complicated even when they have the shallow appearance of being simple
