Aim for Immutability
As programmers, we think a lot about state. Is the user logged in? Can this edge-case ever occur? Is the coffee pot empty again? The problem is, that humans are pretty bad at keeping track of state. That is, unless you're a Chess Grandmaste…
That was a really good read.
And although I also preferred the default being immutability for comprehension reasons, I never though about the runtime.
Biggest meme in programming.