{
description = "hbs2";

inputs = {

    nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";
    # haskell-flake-utils.url = "github:ivanovs-4/haskell-flake-utils";
    flake-utils.url = "github:numtide/flake-utils";
    haskell-flake-utils = { # we don't use haskell-flake-utils directly, but we override input evrywhere
        url = "github:ivanovs-4/haskell-flake-utils/master";
        inputs.flake-utils.follows = "flake-utils";
    };
    hspup.url = "github:voidlizard/hspup";
    hspup.inputs.nixpkgs.follows = "nixpkgs";
    hspup.inputs.haskell-flake-utils.follows = "haskell-flake-utils";

};

outputs = { self, nixpkgs, flake-utils, ... }@inputs:
  flake-utils.lib.eachSystem ["x86_64-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin"]
  (system:
    let
      packageNames =
        topLevelPackages ++ keymanPackages;

      keymanPackages =
        [
        "hbs2-keyman"
        "hbs2-keyman-direct-lib"
        ];

      topLevelPackages =
        [
        "hbs2"
        "hbs2-peer"
        "hbs2-core"
        "hbs2-storage-simple"
        "hbs2-git"
        "hbs2-git-dashboard"
        "hbs2-qblf"
        "hbs2-fixer"
        "hbs2-cli"
        "hbs2-sync"
        "fixme-new"
        ];

      miscellaneous =
        [
        "bytestring-mmap"
        "db-pipe"
        "fuzzy-parse"
        "suckless-conf"
        ];

      pkgs = import nixpkgs {
          inherit system;
          overlays = [defaultOverlay];
        };

      defaultOverlay = final: prev:
        (prev.lib.composeManyExtensions # no-op
        [ overlay
        ]) final prev;

      packagePostOverrides = pkg: with pkgs.haskell.lib.compose; pkgs.lib.pipe pkg [
        disableExecutableProfiling
        disableLibraryProfiling
        dontBenchmark
        dontCoverage
        dontDistribute
        dontHaddock
        dontHyperlinkSource
        doStrip
        enableDeadCodeElimination
        justStaticExecutables

        dontCheck

        (overrideCabal (drv: {
            preBuild = ''
              export GIT_HASH="${self.rev or self.dirtyRev or "dirty"}"
            '';
          }))
      ];


    jailbreakUnbreak = pkg:
        pkgs.haskell.lib.doJailbreak (pkg.overrideAttrs (_: { meta = { }; }));

    makePkgsFromDir = hp: pkgNames: mkPath:
      pkgs.lib.genAttrs pkgNames (name:
        hp.callCabal2nix name "${self}/${mkPath name}" {});

    overlay = final: prev: let pkgs = prev; in
    {
      haskellPackages = pkgs.haskellPackages.override {
        overrides = new: old: with pkgs.haskell.lib;
          {
            scotty = new.callHackage "scotty" "0.21" {};
            skylighting-lucid = new.callHackage "skylighting-lucid" "1.0.4" { };
            wai-app-file-cgi = dontCoverage (dontCheck (jailbreakUnbreak old.wai-app-file-cgi));
          }
          // makePkgsFromDir old topLevelPackages (n: n)
          // makePkgsFromDir old keymanPackages (name: "hbs2-keyman/${name}")
          // makePkgsFromDir old miscellaneous (name: "miscellaneous/${name}");
        };
      };

    makePackages = pkgs:
      pkgs.lib.mapAttrs
        (_name: packagePostOverrides) # we can't apply overrides inside our overlay because it will remove linking info
        (pkgs.lib.getAttrs packageNames pkgs.haskellPackages);

    packagesDynamic = makePackages pkgs;
    packagesStatic = makePackages pkgs.pkgsStatic;

    makeShell = packages_: pkgs.haskellPackages.shellFor {
      packages = _: packages_;
      buildInputs = (
        with pkgs.haskellPackages; [
          ghc
          ghcid
          cabal-install
          haskell-language-server
          hoogle
          # htags
          text-icu
          pkgs.icu72
          pkgs.openssl
          weeder
        ]
        ++
        [ pkgs.pkg-config
          pkgs.libsodium
          pkgs.file
          pkgs.zlib
          inputs.hspup.packages.${pkgs.system}.default
        ]
      );

      shellHook = ''
      export GIT_HASH="${self.rev or self.dirtyRev or "dirty"}"
      '';

    };
    in  {
    legacyPackages = pkgs;
    overlays.default = defaultOverlay;
    homeManagerModules.default = import ./nix/hm-module.nix self;

    packages =
      packagesDynamic //
      {
        default =
        pkgs.symlinkJoin {
          name = "hbs2-all";
          paths = builtins.attrValues packagesDynamic;
        };
        static =
        pkgs.symlinkJoin {
          name = "hbs2-static";
          paths = builtins.attrValues packagesStatic;
        };
      };


    devShells.default = pkgs.haskellPackages.shellFor {
      packages = _:
        pkgs.lib.attrVals packageNames pkgs.haskellPackages ++
        pkgs.lib.attrVals miscellaneous pkgs.haskellPackages;
      # withHoogle = true;
      buildInputs = (
        with pkgs.haskellPackages; [
          ghc
          ghcid
          cabal-install
          haskell-language-server
          hoogle
          threadscope
          eventlog2html
          # htags
          text-icu
          magic
          pkgs.icu72
          pkgs.openssl
          weeder
        ]
        ++
        [ pkgs.pkg-config
          pkgs.libsodium
          pkgs.file
          pkgs.zlib
          inputs.hspup.packages.${pkgs.system}.default
        ]
      );
      unfuck = makeShell [];
    };
  }
 );

}