How to build pip package from source that requires rust toolchain

[rupurt]

Howdy :wave:

I'm trying to add object-store-python as a dependency that will build from source as they haven't released a new pypi version. Is this possible with the current pip module? I've tried adding an override with cargo but it doesn't seem to get picked up.

Collecting object-store-python@ https://github.com/roeap/object-store-python/archive/6144879f3061f298122b28318bcad0a7d4001d09.zip#subdirectory=object-store
  Using cached https://github.com/roeap/object-store-python/archive/6144879f3061f298122b28318bcad0a7d4001d09.zip
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
  Preparing metadata (pyproject.toml) ... error
  error: subprocess-exited-with-error

  × Preparing metadata (pyproject.toml) did not run successfully.
  │ exit code: 1
  ╰─> [6 lines of output]

      Cargo, the Rust package manager, is not installed or is not on PATH.
      This package requires Rust and Cargo to compile extensions. Install it through
      the system's package manager or via https://rustup.rs/

      Checking for Rust toolchain....
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.
error: metadata-generation-failed

  deps = {
    nixpkgs,
    self,
    ...
  }: {
    stdenv = nixpkgs.stdenv;
    python = nixpkgs.python312;
    cargo = nixpkgs.cargo;
  };

  pip = {
    requirementsList =
      pyproject.build-system.requires
      or []
      ++ pyproject.project.dependencies
      ++ lib.optionals (config.flags.groupDev) pyproject.project.optional-dependencies.dev;
    flattenDependencies = true;
    overrideAll.deps.python = lib.mkForce config.deps.python;
    overrides = {
      object-store-python.mkDerivation = {
        buildInputs = [
          config.deps.cargo
        ];
      };
  };