{
  description = "Rust dev env for Meltano toy project";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, flake-utils }:
    flake-utils.lib.eachDefaultSystem (system:
      let
        pkgs = import nixpkgs { inherit system; };
      in {
        devShells.default = pkgs.mkShell {
          buildInputs = with pkgs; [
            rustup
            pkg-config
            openssl
            postgresql
            sqlx-cli
          ];

          shellHook = ''
            export DATABASE_URL="postgres://${POSTGRES_APP_USER}:${POSTGRES_APP_PASSWORD}@${POSTGRES_HOST}:${POSTGRES_APP_PORT}/${POSTGRES_APP_DB}"
            export DW_DATABASE_URL="postgres://${POSTGRES_DW_USER}:${POSTGRES_DW_PASSWORD}@${POSTGRES_HOST}:${POSTGRES_DW_PORT}/${POSTGRES_DW_DB}"
            echo "✅ Rust + PostgreSQL dev env ready"
          '';
        };
      });
}