add custom huggingface_hub packages (learning from hf-cli's authentication workflow)

hosts/packages/huggingface_hub/hf-xet.nix

@@ -0,0 +1,56 @@
+{
+  lib,
+  buildPythonPackage,
+  fetchFromGitHub,
+  pkg-config,
+  rustPlatform,
+  openssl,
+}:
+buildPythonPackage rec {
+  pname = "hf-xet";
+  version = "1.1.5";
+  pyproject = true;
+
+  src = fetchFromGitHub {
+    owner = "huggingface";
+    repo = "xet-core";
+    tag = "v${version}";
+    hash = "sha256-udjZcXTH+Mc4Gvj6bSPv1xi4MyXrLeCYav+7CzKWyhY=";
+  };
+
+  sourceRoot = "${src.name}/hf_xet";
+
+  cargoDeps = rustPlatform.fetchCargoVendor {
+    inherit
+      pname
+      version
+      src
+      sourceRoot
+      ;
+    hash = "sha256-PTzYubJHFvhq6T3314R4aqBAJlwehOqF7SbpLu4Jo6E=";
+  };
+
+  nativeBuildInputs = [
+    pkg-config
+    rustPlatform.cargoSetupHook
+    rustPlatform.maturinBuildHook
+  ];
+
+  buildInputs = [
+    openssl
+  ];
+
+  env.OPENSSL_NO_VENDOR = 1;
+
+  pythonImportsCheck = ["hf_xet"];
+
+  # No tests (yet?)
+  doCheck = false;
+
+  meta = {
+    description = "Xet client tech, used in huggingface_hub";
+    homepage = "https://github.com/huggingface/xet-core/tree/main/hf_xet";
+    changelog = "https://github.com/huggingface/xet-core/releases/tag/v${version}";
+    license = lib.licenses.asl20;
+  };
+}