This repo is primarily LLM-written, but sort-of works as a proof of concept. I don't recommend actually using this in its current state. It needs to be polished up.

A Nix library for seamless, modular, and unpatched CMake integration. See ARCHITECTURE.md for real details.

nix-cmake bridges the gap between CMake's dynamic ecosystem (CPM, FetchContent, RAPIDS) and Nix's reproducible, sandboxed build system. It aims to provide a declarative, uv2nix/crane-style experience for C++ projects.

• Zero-Patch Philosophy: Uses standard Kitware CMake (4.2.1) without the extensive patching typically required by Nixpkgs.
• Dependency Provider Interception: Automatically intercepts FetchContent and CPM calls to provide Nix-managed sources.
• Recursive Discovery: Supports FOD-based exploration of nested dependency trees to build complete dependency graphs.
• File API Integration: Leverages the CMake File API for accurate extraction of project targets and metadata.
• Modular Overlays: Provides a fixed-point API for managing and overriding project dependencies.

{
  inputs.nix-cmake.url = "github:sielicki/nix-cmake";

  outputs = { nix-cmake, nixpkgs, ... }:
    let
      pkgs = nixpkgs.legacyPackages.x86_64-linux;
      workspace = nix-cmake.lib.workspace pkgs;
    in {
      packages.x86_64-linux.default = workspace.buildCMakePackage {
        pname = "my-app";
        version = "0.1.0";
        src = ./.;
        
        # Inject dependencies
        fetchContentDeps = {
          fmt = pkgs.fetchFromGitHub { ... };
        };
      };
    };
}

# Perform a recursive discovery pass
nix build .#discovery --extra-experimental-features "nix-command flakes"

Detailed technical documentation and guides are available in the docs/ directory:

• Architecture - How the dependency provider and unpatched CMake work.
• Recursive Discovery - Exploring multi-level dependency trees.
• API Reference - Detailed signatures for workspace and builder functions.
• Design Vision - Inspiration from crane and uv2nix.
• Roadmap - Current status and future plans.
• Comparisons - Comparison to other *2nix tools and real-world examples.

Apache 2.0