Env vars were a good first try. we can do better (opens in new tab)

Looks interesting and quite a nice website, I'd lose that obviously AI generated "whack a mole" image though: it's over-literal, just plain wrong (why would the guy look at the hammer, should look at the moles, and why so many moles? that's not whack-a-mole) and is going to age really quickly.

Env vars are usually better than the alternatives, but orgs often move beyond them and build their own configuration systems. Why?

One big one is that the way environment variables work fundamentally encourages a small number of variables, which is at odds with the desire to have a highly configurable system.