Thank you for your work! The issue was that my rustup thought stable was 1.86.0. In my ignorance I thought this was something that would be updated along other stuff, seeming as rustup was installed via something else, probably either proto or moon (or both). After I did rustup update, stable changed to 1.88.0, so appears to be no issues now.

@snowman78 I see, you're referring to makedepends, not a runtime dependency. This PKGBUILD depends on cargo (rust or rustup). Currently, the latest rust version published in extra is 1.88.0, so everything should be fine. I've tested it in a clean chroot. If you still encounter issues, please try updating your rust version before building.

I ran yay --editmenu -S aur/proto, edited PKGBUILD to have 1.88 rather than stable, and this got proto to build properly for me (I'm on EndeavourOS if that matters anything). I can understand if you don't want to depend on a specific version, but the last update of proto added minimumsversions (that is where the 1.88.0 comes from).

Hmm, no Rust expert myself, but I don't think that is the correct fix (or the only fix). rustup stable provides 1.86

The latest update 0.51.4-1 gives me these errors:

==> Making package: proto 0.51.4-1 (Tue Jul 22 17:19:57 2025) ==> Checking runtime dependencies... ==> Checking buildtime dependencies... ==> WARNING: Using existing $srcdir/ tree ==> Removing existing $pkgdir/ directory... ==> Starting build()... error: rustc 1.86.0 is not supported by the following packages: proto_cli@0.51.4 requires rustc 1.88.0 proto_cli@0.51.4 requires rustc 1.88.0 proto_core@0.51.5 requires rustc 1.88.0 warpgate@0.26.1 requires rustc 1.88.0

==> ERROR: A failure occurred in build(). Aborting... -> error making: proto-exit status 4

@snowman78 Thank you! I've checked and found that proto uses rustup to install rust, so I've added rustup as an optional dependency.

The latest proto version requires rust 1.88 (at least via warpgate dependency).

proto::shim::missing_binary error fixed in v0.36.1.

@phnx47 Thank you for your investigation and your kindness. For now, I'll resolve my problem by this solution.

By the way, I'm wondering if this is a bug or if there're some reasons for this change. I'll keep an eye on the issue.

Raised issue in the upstream proto#490

As temporary solution you can create a symlink

ln -s /usr/bin/proto-shim ~/.proto/bin/proto-shim

or

ln -s /usr/bin/proto-shim ${PROTO_HOME}/bin/proto-shim

or export PROTO_LOOKUP_DIR

export PROTO_LOOKUP_DIR=/usr/bin

@usagiga Oh, yes, something seems changed, I will investigate it.