> Don't immortalize anything, though. Always reserve the freedom to swap out integrated crates when something better rolls around. That's a non-starter, though

> Don't immortalize anything, though. Always reserve the freedom to swap out integrated crates when something better rolls around. That's a non-starter, though. Once it's in std, it's not an "integrated crate", it's in std, just like any other part of it. Removing it is a breaking change, and I don't want a new incompatible Rust major version every year or two (or even five or ten, honestly). (Of course, Rust has editions to make breaking changes possible without affecting old code, but there are limits to what you can change in editions.) Pretty much every language ecosystem fights really hard to maintain backward compatibility as they evolve, and every time they fail to do that, it causes headaches, sometimes for years. Python 2->3 is of course the canonical painful example of that, but there are others that are instructive if you only take the time to research. (And before you mention something like Zig, which changes incompatibly frequently enough, remember that the author has made an active decision to remain pre-1.0 unstable. That's one reason why the Zig community isn't that large. That's not me looking down on them; that's an active choice they've made, and they're free to make that choice. But bigger/popular languages like Rust can't go back in time and decide to be like that.)