[kibwen]

For the purposes of this discussion the question is not whether or not a crate exposes optional features that require a nightly compiler, but whether or not a crate makes use of the nightly compiler mandatory, which has become extremely rare in my experience. Perhaps it's more common in some embedded use cases, but if people want to make that assertion, I would ask that they either mention which libraries they're specifically talking about or which nightly features they're specifically referring to.

[estebank]

I think the divide is apps vs libraries: a library that requires their dependants to set an environment variable opting out of stability guarantees is unlikely to gain adoption, but applications that do so are more common, like Firefox.

[SkiFire13]

> For the purposes of this discussion the question is not whether or not a crate exposes optional features that require a nightly compiler, but whether or not a crate makes use of the nightly compiler mandatory

In my opinion what matters is the functionality. If it's provided by a nightly-only crate or as a nightly-only feature of an otherwise non-nightly-only crate it doesn't really matter.

But I agree that this is become more and more rare.