flake.nix

{
    description = "Minimal devshell flake for haskell";

    inputs.haskellNix.url = "github:input-output-hk/haskell.nix";
    inputs.nixpkgs.follows = "haskellNix/nixpkgs-unstable";
    inputs.flake-utils.url = "github:numtide/flake-utils";

    outputs = { self, nixpkgs, flake-utils, haskellNix }:
    let overlays = {
         crypto = final: prev: {
          libsodium-vrf = final.callPackage ({ stdenv, lib, fetchFromGitHub, autoreconfHook }:
            stdenv.mkDerivation {
                name = "libsodium-1.0.18";

                src = fetchFromGitHub {
                    owner = "input-output-hk";
                    repo = "libsodium";
                    rev = "11bb20dba02b013bf1d83e3c16c51eab2ff07efc";
                    sha256 = "1h9fcwra610vmh0inkdkqs3bfs83xl5dk146dqx440wwh9pn4n4w";
                };

                nativeBuildInputs = [ autoreconfHook ];

                configureFlags = [ "--enable-static" ];

                outputs = [ "out" "dev" ];
                separateDebugInfo = stdenv.isLinux && stdenv.hostPlatform.libc != "musl";

                enableParallelBuilding = true;

                doCheck = true;

                meta = with lib; {
                    description = "A modern and easy-to-use crypto library - VRF fork";
                    homepage = "http://doc.libsodium.org/";
                    license = licenses.isc;
                    maintainers = [ "tdammers" "nclarke" ];
                    platforms = platforms.all;
                };
            }) {};
        };
        # add static-$pkg for a few packages to be able to pull them im explicitly.
        static-libs = (final: prev: {
          static-libsodium-vrf = final.libsodium-vrf.overrideDerivation (old: {
            configureFlags = old.configureFlags ++ [ "--disable-shared" ];
          });
          static-secp256k1 = final.secp256k1.overrideDerivation (old: {
            configureFlags = old.configureFlags ++ ["--enable-static" "--disable-shared" ];
          });
          static-gmp = (final.gmp.override { withStatic = true; }).overrideDerivation (old: {
            configureFlags = old.configureFlags ++ ["--enable-static" "--disable-shared" ];
          });
          static-openssl = (final.openssl.override { static = true; });
          static-zlib = final.zlib.override { shared = false; };
          static-pcre = final.pcre.override { shared = false; };
        });
         # the haskell inline-r package depends on internals of the R
         # project that have been hidden in R 4.2+. See
         # https://github.com/tweag/HaskellR/issues/374
         oldR = (final: prev: {
           R_4_1_3 = final.R.overrideDerivation (old: rec {
             version = "4.1.3";
             patches = []; # upstream patches will most likely break this build, as they are specific to a different version.
             src = final.fetchurl {
               url = "https://cran.r-project.org/src/base/R-${final.lib.versions.major version}/${old.pname}-${version}.tar.gz";
               sha256 = "sha256-Ff9bMzxhCUBgsqUunB2OxVzELdAp45yiKr2qkJUm/tY="; };
             });
         });
         cddl-tools = (final: prev: {
          cbor-diag = final.callPackage ./pkgs/cbor-diag { };
          cddl = final.callPackage ./pkgs/cddl { };
         });
       };
       supportedSystems = [
            "x86_64-linux"
            "x86_64-darwin"
            "aarch64-linux"
            "aarch64-darwin"
       ];
    in flake-utils.lib.eachSystem supportedSystems (system:
         let
           pkgs = import nixpkgs {
             overlays = [haskellNix.overlay] ++ builtins.attrValues overlays;
             inherit system;
             inherit (haskellNix) config;
           };
         in rec {
           # These are for checking IOG projects build in an environment
           # without haskell packages built by haskell.nix.
           #
           # Usage:
           #
           # nix develop github:input-output-hk/devx#ghc924 --no-write-lock-file -c cabal build
           #
           devShells =
             let compilers = pkgs: builtins.removeAttrs pkgs.haskell-nix.compiler
               # Exclude old versions of GHC to speed up `nix flake check`
               [ "ghc844"
                 "ghc861" "ghc862" "ghc863" "ghc864" "ghc865"
                 "ghc881" "ghc882" "ghc883" "ghc884"
                 "ghc8101" "ghc8102" "ghc8103" "ghc8104" "ghc8105" "ghc8106" "ghc810420210212"
                 "ghc901"
                 "ghc921" "ghc922" "ghc923" "ghc924"];
                 static-pkgs = if pkgs.stdenv.hostPlatform.isLinux
                               then if pkgs.stdenv.hostPlatform.isAarch64
                                    then pkgs.pkgsCross.aarch64-multiplatform-musl
                                    else pkgs.pkgsCross.musl64
                               else pkgs;
             in (builtins.mapAttrs (compiler-nix-name: compiler:
                  import ./dynamic.nix { inherit pkgs compiler compiler-nix-name; }
                  ) (compilers pkgs)
              // pkgs.lib.mapAttrs' (compiler-nix-name: compiler:
                  pkgs.lib.nameValuePair "${compiler-nix-name}-minimal" (
                    import ./dynamic.nix { inherit pkgs compiler compiler-nix-name; withHLS = false; withHlint = false; }
                  )) (compilers pkgs)
              // pkgs.lib.mapAttrs' (compiler-nix-name: compiler:
                  pkgs.lib.nameValuePair "${compiler-nix-name}-static" (
                    import ./static.nix { pkgs = static-pkgs; inherit compiler compiler-nix-name; }
                  )) (compilers static-pkgs.buildPackages)
              // pkgs.lib.mapAttrs' (compiler-nix-name: compiler:
                  pkgs.lib.nameValuePair "${compiler-nix-name}-static-minimal" (
                    import ./static.nix { pkgs = static-pkgs; inherit compiler compiler-nix-name; withHLS = false; withHlint = false; }
                  )) (compilers static-pkgs.buildPackages)
             );
        hydraJobs = devShells;
       });

    # --- Flake Local Nix Configuration ----------------------------
    nixConfig = {
      extra-substituters = [
        "https://cache.iog.io"
        # We only have zw3rk cache in here, because it provide aarch64-linux and aarch64-darwin.
        "https://cache.zw3rk.com"
      ];
      extra-trusted-public-keys = [
        "hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ="
        "loony-tools:pr9m4BkM/5/eSTZlkQyRt57Jz7OMBxNSUiMC4FkcNfk="
      ];
      # post-build-hook = "./upload-to-cache.sh";
      allow-import-from-derivation = "true";
    };
    # --------------------------------------------------------------
}