uv2nix_hammer_overrides

uv2nix does not contain an override collection by design.

The uv2nix_hammer is a tool to automatically generate such overrides on demand.

These overrides are then collected in this repository so that downstream users can easily use uv2nix for the most common python packages.

Current state (2024-09-18): I have done a sweep through the 15.6k 'most important' python packages, prefering wheels. About 13.4k build, another 1000 have ended up on the exclusion list for various reasons, and the remaining ~800 are in limbo.

Poetry2nix might also benefit from these overrides, there's an example how to use them below.

Usage:

Example flake.nix:

{
  description = "A basic flake using uv2nix";

  inputs.uv2nix.url = "github:adisbladis/uv2nix";
  inputs.uv2nix.inputs.nixpkgs.follows = "nixpkgs";

  inputs.uv2nix_hammer_overrides.url = "github:TyberiusPrime/uv2nix_hammer";
  inputs.uv2nix_hammer_overrides.inputs.nixpkgs.follows = "nixpkgs";

  inputs.nixpkgs_master.url = "github:nixos/nixpkgs/master";

  # Disclaimer: Uv2nix is new and experimental.
  # Users are expected to be able to contribute fixes.

  outputs = {
    nixpkgs,
    uv2nix,
    uv2nix_hammer_overrides,
    nixpkgs_master,
    ...
  }: let
    inherit (nixpkgs) lib;

    # Load a uv workspace from a workspace root.
    # Uv2nix treats all uv projects as workspace projects.
    workspace = uv2nix.lib.workspace.loadWorkspace {workspaceRoot = ./.;};

    # Manage overlays
    overlay = let
      # Create overlay from workspace.
      overlay' = workspace.mkOverlay {
        # Prefer prebuilt binary wheels as a package source.
        # Sdists are less likely to "just work" because of the metadata missing from uv.lock.
        # Binary wheels are more likely to, but may still require overrides for library dependencies.
        sourcePreference = "sdist"; # or sourcePreference = "sdist";
        # Optionally customise PEP 508 environment
        # environ = {
        #   platform_release = "5.10.65";
        # };
      };

      # Uv2nix can only work with what it has, and uv.lock is missing essential metadata to perform some builds.
      # This is an additional overlay implementing build fixups.
      # See:
      # - https://adisbladis.github.io/uv2nix/FAQ.html
      # - https://nixos.org/manual/nixpkgs/stable/#overriding-python-packages
      overrides =
        lib.composeExtensions
        (uv2nix_hammer_overrides.overrides)
        (_final: prev: {
        # if you need even more overrides
        });
      #overrides = ;
    in
      lib.composeExtensions overlay' overrides;

    # This example is only using x86_64-linux
    pkgs = nixpkgs.legacyPackages.x86_64-linux;

    # Create an overriden interpreter
    python = pkgs.python3.override {
      # Note the self argument.
      # It's important so the interpreter/set is internally consistent.
      self = python;
      # Pass composed Python overlay to the interpreter
      packageOverrides = overlay;
    };
  in {
    # 'app' is the name in pyproject.toml after name normalization.
    # See https://packaging.python.org/en/latest/specifications/name-normalization/#normalization

    packages.x86_64-linux.default =
      python.withPackages (p: [p.app]);
    # TODO: A better mkShell withPackages example.
    devShells.x86_64-linux.default = pkgs.mkShell {
      inputsFrom = [python.pkgs.app];
      packages = [pkgs.uv];
    };
    devShells.x86_64-linux.uv = pkgs.mkShell {
      packages = [nixpkgs_master.legacyPackages.x86_64-linux.uv];
    };
  };
}

poetry2nix example

{
  description = "Application packaged using poetry2nix";

  inputs = {
    flake-utils.url = "github:numtide/flake-utils";
    nixpkgs.url = "github:NixOS/nixpkgs/24.05";
    poetry2nix = {
      url = "github:nix-community/poetry2nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    uv2nix_hammer_overrides.url = "github:/TyberiusPrime/uv2nix_hammer_overrides";
    uv2nix_hammer_overrides.inputs.nixpkgs.follows = "nixpkgs";
  };

  outputs = {
    self,
    nixpkgs,
    flake-utils,
    poetry2nix,
    uv2nix_hammer_overrides,
  }:
    flake-utils.lib.eachDefaultSystem (system: let
      pkgs = nixpkgs.legacyPackages.${system};
      inherit (poetry2nix.lib.mkPoetry2Nix {inherit pkgs;}) mkPoetryEnv defaultPoetryOverrides;
    in {
      packages = {
        myapp = mkPoetryEnv {
          projectDir = self;
          python = pkgs.python312;
          overrides = [
            # defaultPoetryOverrides # depending on wether you want the poetry2nix overrides as well
            (uv2nix_hammer_overrides.overrides pkgs)
          ];

          preferWheels = true;
        };
      };

      defaultPackage = self.packages.${system}.myapp;

      # Shell for app dependencies.
      devShells.default = pkgs.mkShell {
        inputsFrom = [self.packages.${system}.myapp];
      };

      # Shell for poetry.
      devShells.poetry = pkgs.mkShell {
        packages = [pkgs.poetry];
      };
    });
}

Open tasks:

• Fix (or exclude) the remaining build failures
• Redo it without '--wheel', prefering source packages (for the target packages).
• Mabye do it without preferWheel for all packages