Simplify Nix build

Author: samuelburnham

.github/workflows/ci.yml

@@ -33,4 +33,4 @@ jobs:
         with:
           name: argumentcomputer
           authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
-      - run: nix run .#test
+      - run: nix build

flake.lock

@@ -1,13 +1,12 @@
 {
-  description = "Lean 4 Example Project";
+  description = "LSpec Nix Flake";
 
   inputs = {
-    nixpkgs.url = "github:nixos/nixpkgs/nixos-24.11";
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
     flake-parts.url = "github:hercules-ci/flake-parts";
     lean4-nix = {
       url = "github:argumentcomputer/lean4-nix";
       inputs.nixpkgs.follows = "nixpkgs";
-      #rev = "";
     };
   };
 
@@ -25,30 +24,24 @@
         "x86_64-linux"
       ];
 
-      flake = {
-        lib = import ./lspec.nix;
-      };
-
       perSystem = {
         system,
         pkgs,
         self',
         config,
         ...
       }:
-        let
-          lib = (import ./lspec.nix { inherit pkgs lean4-nix; }).lib;
-          lspecBin = lib.lspecLib.executable;
-        in
       {
         _module.args.pkgs = import nixpkgs {
           inherit system;
           overlays = [(lean4-nix.readToolchainFile ./lean-toolchain)];
         };
-        # TODO: Replace with a Nix-compatible binary
-        # Running `lspecBin` will cause an error due to calling `lake` explicitly and only parsing `lakefile.lean` files
-        # It is included for completeness only
-        #packages.default = lspecBin;
+
+        # Build the library with `nix build`
+        packages.default = ((lean4-nix.lake {inherit pkgs;}).mkPackage {
+            src = ./.;
+            roots = ["LSpec"];
+        }).modRoot;
 
         devShells.default = pkgs.mkShell {
           packages = with pkgs.lean; [lean lean-all];