question: how do you specify abi when cross compiling

[GlennWSo]

I want to cross compile to target:
aarch64-unknown-linux-musl

But using when a follow the get started tutorial and do a build with:

nix build .#aarch64-linux.dev.hello-flakebox a get a file of aarch64-unknown-linux-gnu

How do i declare the -musl part?

[dpc]

It needs to be added as a new "target", possibly with matching "toolchain".