Attempt to fix the mapping of each system

flake.nix

@@ -23,7 +23,24 @@
       treefmt-nix,
     }:
     let
-      forEachSystem = systems: map: nixpkgs.lib.genAttrs systems map;
+      eachSystemOp =
+        op: systems: f:
+        builtins.foldl' (op f) { } systems;
+      mapEachSystem = eachSystemOp (
+        f: attrs: system:
+        let
+          result = f system;
+        in
+        builtins.foldl' (
+          attrs: key:
+          attrs
+          // {
+            ${key} = (attrs.${key} or { }) // {
+              ${system} = result.${key};
+            };
+          }
+        )
+      );
     in
     {
       lib.mkFlake =
@@ -44,9 +61,8 @@
             "treeFmtFile"
           ];
         in
-        (
         (snowfall-lib.mkFlake snowfallOptions)
-          // (forEachSystem systems (
+        // (mapEachSystem systems (
           system:
           let
             pkgs = import nixpkgs { inherit system; };
@@ -64,7 +80,6 @@
               ] ++ (devShellPackages pkgs);
             };
           }
-          ))
-        );
+        ));
     };
 }