improvise/flake.nix

{
  description = "Improvise — Multi-Dimensional Data Modeling Terminal Application";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    rust-overlay = {
      url = "github:oxalica/rust-overlay";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, rust-overlay, flake-utils }:
    flake-utils.lib.eachDefaultSystem (system:
      let
        overlays = [ (import rust-overlay) ];
        pkgs = import nixpkgs { inherit system overlays; };
        isLinux = pkgs.lib.hasInfix "linux" system;

        rustToolchain = pkgs.rust-bin.stable.latest.default.override {
          extensions = [ "rust-src" "clippy" "rustfmt" ];
          targets = pkgs.lib.optionals isLinux [ "x86_64-unknown-linux-musl" ];
        };
      in
      {
        devShells.default = pkgs.mkShell ({
          nativeBuildInputs = [
            rustToolchain
            pkgs.pkg-config
          ] ++ pkgs.lib.optionals isLinux [
            # Provide cc (gcc) for building proc-macro / build-script crates
            # that target the host (x86_64-unknown-linux-gnu).
            pkgs.gcc
            # musl-gcc wrapper for the static musl target.
            pkgs.pkgsMusl.stdenv.cc
          ];

          RUST_BACKTRACE = "1";
        } // pkgs.lib.optionalAttrs isLinux {
          # Tell Cargo which linker to use for each target so it never
          # falls back to rust-lld (which can't find glibc on NixOS).
          CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_LINKER =
            "${pkgs.gcc}/bin/gcc";
          CARGO_TARGET_X86_64_UNKNOWN_LINUX_MUSL_LINKER =
            "${pkgs.pkgsMusl.stdenv.cc}/bin/cc";

          # Default build target: static musl binary.
          CARGO_BUILD_TARGET = "x86_64-unknown-linux-musl";
        });

        packages.default =
          if isLinux then
            (pkgs.pkgsMusl.makeRustPlatform {
              cargo = rustToolchain;
              rustc = rustToolchain;
            }).buildRustPackage {
              pname = "improvise";
              version = "0.1.0";
              src = ./.;
              cargoLock.lockFile = ./Cargo.lock;
            }
          else
            (pkgs.makeRustPlatform {
              cargo = rustToolchain;
              rustc = rustToolchain;
            }).buildRustPackage {
              pname = "improvise";
              version = "0.1.0";
              src = ./.;
              cargoLock.lockFile = ./Cargo.lock;
            };
      });
}