{
  description = "SOTA Rails 8 Native Environment & OCI Image for JamKazam Admin - Cache Bust 2";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    nix2container.url = "github:nlewo/nix2container";
  };

  outputs = { self, nixpkgs, nix2container }: 
    let
      supportedSystems = [ "x86_64-linux" "aarch64-linux" "aarch64-darwin" ];
      forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
    in {
      # Track 1: The Native Inner Loop (for 8GB RAM Macs)
      devShells = forAllSystems (system: {
        default = let pkgs = import nixpkgs { inherit system; }; in
          pkgs.mkShell {
            buildInputs = with pkgs; [
              ruby_3_4
              postgresql_16.lib
              jemalloc
              libyaml
              vips
              bun # for ci/watch.ts
              git
            ];
            shellHook = ''
              export RUBY_YJIT_ENABLE=1
              export RAILS_ENV=development
              # macOS uses .dylib, Linux uses .so
              if [ "$(uname)" = "Darwin" ]; then
                export LD_PRELOAD="${pkgs.jemalloc}/lib/libjemalloc.dylib"
              else
                export LD_PRELOAD="${pkgs.jemalloc}/lib/libjemalloc.so"
              fi
              echo "🚀 SOTA Shell Ready (YJIT + jemalloc enabled)"
            '';
          };
      });

      # Track 2: The Production OCI Image
      packages = forAllSystems (system:
        let
          pkgs = import nixpkgs { inherit system; };
          n2c = nix2container.packages.${system};
          
          # 1. Define the Ruby Environment with common native gems pre-installed
          rubyEnv = pkgs.ruby_3_4.withPackages (ps: with ps; [ 
            psych
            pg
            nokogiri
          ]);

          # 2. Join dev and lib outputs for common dependencies
          libyaml-joined = pkgs.symlinkJoin { name = "libyaml-joined"; paths = [ pkgs.libyaml pkgs.libyaml.dev ]; };
          openssl-joined = pkgs.symlinkJoin { name = "openssl-joined"; paths = [ pkgs.openssl pkgs.openssl.dev ]; };
          postgres-joined = pkgs.symlinkJoin { name = "postgres-joined"; paths = [ pkgs.postgresql_16 pkgs.postgresql_16.lib ]; };

          # 3. Aggregate all dependencies into a single environment
          allDeps = pkgs.buildEnv {
            name = "jam-admin-env";
            paths = with pkgs; [
              rubyEnv
              postgres-joined
              libyaml-joined
              openssl-joined
              zlib.dev
              zlib
              libiconv
              libxml2
              libxml2.dev
              libxslt
              libxslt.dev
              jemalloc
              vips
              bash
              coreutils
              git
              gnumake
              gcc
              pkg-config
              binutils
            ];
          };

          # 4. A startup script to ensure we are in the right place
          start-jam-admin = pkgs.writeShellScriptBin "start-jam-admin" ''
            export PATH=${allDeps}/bin:$PATH
            export LD_LIBRARY_PATH=${allDeps}/lib:$LD_LIBRARY_PATH
            export PKG_CONFIG_PATH=${allDeps}/lib/pkgconfig
            
            cd /jam-cloud/admin
            
            echo "🔧 Configuring bundler for native extensions..."
            bundle config build.psych --with-yaml-dir=${libyaml-joined}
            bundle config build.pg --with-pg-config=${postgres-joined}/bin/pg_config
            
            echo "💎 Installing gems..."
            bundle install
            
            echo "🚀 Starting Rails..."
            exec bundle exec rails server -b 0.0.0.0
          '';

          appImage = pkgs.dockerTools.buildLayeredImage {
            name = "jamkazam-admin-v3";
            tag = "local";
            config = {
              Cmd = [ "${start-jam-admin}/bin/start-jam-admin" ];
              Env = [ 
                "RUBY_YJIT_ENABLE=1"
                "LD_PRELOAD=${pkgs.jemalloc}/lib/libjemalloc.so"
                "RAILS_ENV=production"
                "RAILS_SERVE_STATIC_FILES=true"
                "PKG_CONFIG_PATH=${allDeps}/lib/pkgconfig"
              ];
              ExposedPorts = { "3000/tcp" = {}; };
            };
            contents = [ 
              allDeps 
              start-jam-admin
              pkgs.libyaml.dev
              pkgs.openssl.dev
              pkgs.postgresql_16.lib
              pkgs.zlib.dev
            ];
          };
        in {
          inherit appImage;
          appImageTarball = appImage;
        }
      );
    };
}