A minimally functional flake utility library for Haskell projects

This is based heavily on
https://github.com/JonathanLorimer/templates/blob/main/template/haskell/flake.nix
but I like libraries a lot more than I like code generation.

There's some more pieces that are probably useful commented out.

flake.nix

+{
+  description = "a Nix flake library for Haskell projects";
+
+  inputs = {
+    flake-utils.url = github:numtide/flake-utils;
+    flake-utils.inputs.nixpkgs.follows = "nixpkgs";
+    pre-commit-hooks.url = github:cachix/pre-commit-hooks.nix;
+    pre-commit-hooks.inputs.nixpkgs.follows = "nixpkgs";
+    pre-commit-hooks.inputs.flake-utils.follows = "flake-utils";
+  };
+
+  outputs = {
+    self,
+    nixpkgs,
+    pre-commit-hooks,
+    flake-utils,
+  }: {
+    lib = import ./lib.nix {
+      inherit self nixpkgs pre-commit-hooks flake-utils;
+    };
+  };
+}

lib.nix

+# Define a library of functionality for constructing Flakes.
+{ pre-commit-hooks, flake-utils, ... }:
+{ pkgs
+# ^ A nixpkgs to use.
+
+, src
+# ^ The source of the Haskell library/project to customize the library for.
+
+, compilerVersion
+# ^ A string giving the version of ghc and related packages to use.
+
+, packageName
+  # ^ A string giving the name of the project/package being packaged.
+}:
+let
+  hsPkgs = pkgs.haskell.packages.${compilerVersion}.override {
+    overrides = hfinal: hprev: {
+      ${packageName} = hfinal.callCabal2nix packageName src {};
+    };
+  };
+in
+rec {
+  checks = { }: {
+    pre-commit-check = preCommitCheck { };
+  };
+
+  preCommitCheck = { }:
+    pre-commit-hooks.lib.${pkgs.system}.run {
+      inherit src;
+      hooks = {
+        alejandra.enable = true;
+        fourmolu.enable = true;
+        cabal-fmt.enable = true;
+      };
+    };
+
+  devShells = { }: {
+    default = hsPkgs.shellFor {
+      inherit (preCommitCheck { }) shellHook;
+      packages = p: [
+      ];
+    buildInputs = with pkgs;
+      [
+        cabal2nix
+    #     haskellPackages.cabal-fmt
+        haskellPackages.cabal-install
+    #     haskellPackages.fourmolu
+    #     haskellPackages.ghcid
+    #     hsPkgs.haskell-language-server
+    #     nodePackages.serve
+      ];
+    };
+  };
+
+  packages = { }: flake-utils.lib.flattenTree rec {
+    default = hsPkgs.${packageName};
+    ${packageName} = default;
+  };
+
+  # haskellDevShell = { pkgs, system, haskellPackageName, src }:
+  #   let
+  #     hsPkgs' = hsPkgs {
+  #       inherit pkgs compilerVersion haskellPackageName src;
+  #     };
+  #   in hsPkgs'.shellFor {
+  #     inherit (preCommitCheck { inherit system src; }) shellHook;
+  #     withHoogle = true;
+  #     packages = p: [
+  #       p.${haskellPackageName} # tahoe-lafs-immutable-uploader
+  #     ];
+  #     buildInputs = with pkgs;
+  #       [
+  #         cabal2nix
+  #         haskellPackages.cabal-fmt
+  #         haskellPackages.cabal-install
+  #         haskellPackages.fourmolu
+  #         haskellPackages.ghcid
+  #         hsPkgs.haskell-language-server
+  #         nodePackages.serve
+  #       ]
+  #       ++ (builtins.attrValues (import ./scripts.nix {
+  #         s = pkgs.writeShellScriptBin;
+  #       }));
+  #   };
+
+}

scripts.nix

+{...}: {
+}