Add support for pre-compiled Alpine (musl) binaries

[onedr0p]

Is your feature request related to a problem? Please describe.

I would like to use rq in Alpine Linux on arm64 and amd64

Currently pre-compiled does not work with gnu on Alpine:

321c5c391439:/usr/local/bin$ rq '$.key' --json '{"key":"value","key":"other value"}'
bash: /usr/local/bin/rq: cannot execute: required file not found

Describe the solution you'd like

Build for MUSL

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.

[github-actions]

Tagging @V0ldek for notifications

[V0ldek]

Hello, thanks for your issue

Do you mean a precompiled library for aarch64-unknown-linux-musl? As a general rule we officially only do CI/CD for Tier 1 Rust targets, and that'd be Tier 2 (see here).

Is there a specific reason you cannot use cargo install or compile from source?

[onedr0p]

Is there a specific reason you cannot use cargo install or compile from source?

I'm looking to embed this tool into a container based on Alpine. Rust isn't known for it's speed when compiling, sure I could do a multi stage build with Docker but it takes so long especially on qemu when trying to build multiarch container images. Having precompiled musl binaries would eleveate this concern as it's built once here and can be pulled in easily in container images based on Alpine that's either arm64 or amd64.

Besides the tiering concern is there any technical limitation to supporting musl? It's sad that Rust doesn't qualify musl as tier 1 since it's been around way longer than Apple silicon.

[V0ldek]

Rust isn't known for it's speed when compiling, sure I could do a multi stage build with Docker but it takes so long especially on qemu when trying to build multiarch container images.

That's very much a good reason, rq is known to be slow to build (specifically to link).

Besides the tiering concern is there any technical limitation to supporting musl?

No, there should not be. Both aarch64-unknown-linux-musl and x86_64-unknown-linux-musl build with no issues for me locally.

The main concern here is limiting maintenance load. Tier 1 seems as a sensible cutoff for me, since at least there is a guarantee from the Rust team that it passes all their tests. Even on Tier 1 we sometimes get hard to debug issues (e.g. currently Windows targets fail to build on nightly due to an obscure linker issue I can't quite track down). A secondary technical issue is building for ARM, as there are no GitHub runners for that and we're self-hosting from a small Raspberry Pi that gets quite computationally hammered even with just building and testing aarch64-unknown-linux-gnu.

Maybe a halfway solution would be to also apply tiering and just build the binaries for rq on release without any additional guarantees (i.e. no tests ran)? I would expect musl to be stable enough for that. I cannot find info on why musl are not Tier 1 targets for Rust, are there some issues or is it just lack of interest or developer resources in the Rust team?

[onedr0p]

as there are no GitHub runners for that

GitHub added support for ARM64 runners not to long ago, you can build via runs-on: ubuntu-24.04-arm

Maybe a halfway solution would be to also apply tiering and just build the binaries for rq on release without any additional guarantees (i.e. no tests ran)? I would expect musl to be stable enough for that.

That would be very nice 😄