From 0b12c690c53b5d98d8fc75e2469eff1c4f08a7e3 Mon Sep 17 00:00:00 2001
From: Benjamin Sparks <b.sparks@alugha.com>
Date: Fri, 30 May 2025 02:21:26 +0200
Subject: [PATCH] python3Packages.uv: reuse already built uv binary

master: `nix-build -A python3Packages.uv` - `0.59s user 0.19s system 0% cpu 12:01.12 total`
branch: `nix-build -A python3Packages.uv` - `1.55s user 0.15s system 7% cpu 9.331 total`
---
 .../development/python-modules/uv/default.nix | 51 +++++++++++--------
 pkgs/top-level/python-packages.nix            |  2 +-
 2 files changed, 31 insertions(+), 22 deletions(-)

diff --git a/pkgs/development/python-modules/uv/default.nix b/pkgs/development/python-modules/uv/default.nix
index 726a861372db..2ab81cf60602 100644
--- a/pkgs/development/python-modules/uv/default.nix
+++ b/pkgs/development/python-modules/uv/default.nix
@@ -1,36 +1,45 @@
 {
   buildPythonPackage,
-  installShellFiles,
-  rustPlatform,
-  pkgs,
-  versionCheckHook,
+  hatchling,
+  lib,
+  uv,
 }:
 
 buildPythonPackage {
-  inherit (pkgs.uv)
+  inherit (uv)
     pname
     version
     src
-    cargoDeps
     meta
-    cargoBuildFlags
-    postInstall
-    versionCheckProgramArg
     ;
+  pyproject = true;
 
-  postPatch = ''
-    substituteInPlace python/uv/_find_uv.py \
-      --replace-fail '"""Return the uv binary path."""' "return '$out/bin/uv'"
+  build-system = [ hatchling ];
+
+  postPatch =
+    # Do not rely on path lookup at runtime to find the uv binary.
+    # Use the propagated binary instead.
+    ''
+      substituteInPlace python/uv/_find_uv.py \
+        --replace-fail '"""Return the uv binary path."""' "return '${lib.getExe uv}'"
+    ''
+    # Sidestep the maturin build system in favour of reusing the binary already built by nixpkgs,
+    # to avoid rebuilding the uv binary for every active python package set.
+    + ''
+      substituteInPlace pyproject.toml \
+        --replace-fail 'requires = ["maturin>=1.0,<2.0"]' 'requires = ["hatchling"]' \
+        --replace-fail 'build-backend = "maturin"' 'build-backend = "hatchling.build"'
+
+      cat >> pyproject.toml <<EOF
+      [tool.hatch.build]
+      packages = ['python/uv']
+
+      EOF
+    '';
+
+  postInstall = ''
+    mkdir -p $out/bin && ln -s ${lib.getExe uv} $out/bin/uv
   '';
 
-  nativeBuildInputs = [
-    installShellFiles
-    rustPlatform.cargoSetupHook
-    rustPlatform.maturinBuildHook
-  ];
-
-  nativeCheckInputs = [ versionCheckHook ];
-
-  pyproject = true;
   pythonImportsCheck = [ "uv" ];
 }
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index 764bab2093a5..ada07cfb99f4 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -18639,7 +18639,7 @@ self: super: with self; {
 
   uuid6 = callPackage ../development/python-modules/uuid6 { };
 
-  uv = callPackage ../development/python-modules/uv { };
+  uv = callPackage ../development/python-modules/uv { inherit (pkgs) uv; };
 
   uv-build = callPackage ../development/python-modules/uv-build { };