rust-nix-musl-dyn

.envrc

use flake

.gitignore

/target/
/.direnv/
/result

Cargo.lock

# This file is automatically @generated by Cargo.
# It is not intended for manual editing.
version = 3

[[package]]
name = "rust-musl-hello"
version = "0.1.0"

Cargo.toml

[package]
name = "rust-musl-hello"
version = "0.1.0"
edition = "2021"

[[bin]]
name = "rust-musl-hello"
path = "main.rs"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]

flake.lock

{
  "nodes": {
    "nixpkgs": {
      "locked": {
        "lastModified": 1708093448,
        "narHash": "sha256-gohEm3/NVyu7WINFhRf83yJH8UM2ie/KY9Iw3VN6fiE=",
        "owner": "nixos",
        "repo": "nixpkgs",
        "rev": "c7763249f02b7786b4ca36e13a4d7365cfba162f",
        "type": "github"
      },
      "original": {
        "owner": "nixos",
        "ref": "nixpkgs-unstable",
        "repo": "nixpkgs",
        "type": "github"
      }
    },
    "root": {
      "inputs": {
        "nixpkgs": "nixpkgs"
      }
    }
  },
  "root": "root",
  "version": 7
}

flake.nix

{
  description = "Hello world Rust program statically linked against musl";

  inputs.nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";

  outputs = { nixpkgs, ... }:
    let
      supportedSystems = [ "x86_64-linux" "aarch64-linux" ];
      forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
      mk = localSystem: crossSystem: rec {
        systems = (if localSystem == crossSystem then {
          system = localSystem;
        } else {
          inherit crossSystem localSystem;
        });
        pkgs = (import nixpkgs systems).pkgsMusl;
        main = pkgs.rustPlatform.buildRustPackage {
          pname = "rust-musl-hello";
          version = "0.1.0";
          src = ./.;
          cargoLock = { lockFile = ./Cargo.lock; };
        };
        image = pkgs.dockerTools.streamLayeredImage {
          name = "rust-musl-dynamic-hello";
          tag = "latest";
          contents = [ pkgs.busybox main ];
          config = { Cmd = [ "/bin/rust-musl-hello" ]; };
        };
      };
    in {
      packages = forAllSystems
        (localSystem: { default = (mk localSystem localSystem).main; });
      apps = forAllSystems (localSystem:
        let
          mkAI = remoteSystem: {
            type = "app";
            program = toString (mk localSystem remoteSystem).image;
          };
        in {
          mkImageI = mkAI "x86_64-linux";
          mkImageA = mkAI "aarch64-linux";
        });

      devShells = forAllSystems (system:
        let pkgs = import nixpkgs { inherit system; };
        in {
          default = pkgs.mkShell { buildInputs = with pkgs; [ cargo nixfmt ]; };
        });
    };
}

main.rs

fn main() {
    println!("Hello, world!");
}