Switch to using my fork of nixpkgs.

nix/configuration/flake.lock

@@ -190,11 +190,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1756563619,
-        "narHash": "sha256-BkZ7NQYR2ZZtNVPyqVomnKUuWMhJy8TYYhQoJNtAvhk=",
+        "lastModified": 1756692750,
+        "narHash": "sha256-5n58fYrcMlPZB/xvj/yD53Lx+4I2pswUT4Zz3S0tnn0=",
         "ref": "og-amd-debug-tools",
-        "rev": "5b8e3fc1b9c5c0d370400c4c727d7cd18a4859a1",
-        "revCount": 853095,
+        "rev": "977f46c905217623642e46eeb259044635bba4d2",
+        "revCount": 854038,
         "type": "git",
         "url": "https://github.com/tomalexander/nixpkgs.git"
       },
@@ -238,11 +238,11 @@
     },
     "nixpkgs-unoptimized": {
       "locked": {
-        "lastModified": 1756563619,
-        "narHash": "sha256-BkZ7NQYR2ZZtNVPyqVomnKUuWMhJy8TYYhQoJNtAvhk=",
+        "lastModified": 1756692750,
+        "narHash": "sha256-5n58fYrcMlPZB/xvj/yD53Lx+4I2pswUT4Zz3S0tnn0=",
         "ref": "og-amd-debug-tools",
-        "rev": "5b8e3fc1b9c5c0d370400c4c727d7cd18a4859a1",
-        "revCount": 853095,
+        "rev": "977f46c905217623642e46eeb259044635bba4d2",
+        "revCount": 854038,
         "type": "git",
         "url": "https://github.com/tomalexander/nixpkgs.git"
       },

nix/configuration/roles/optimized_build/default.nix

@@ -126,6 +126,15 @@
                 }
               );
             })
+            # (final: prev: {
+            #   pythonPackagesOverlays = prev.pythonPackagesOverlays.extend (
+            #     final': prev': {
+            #       inherit (pkgs-unoptimized.pythonPackagesOverlays)
+            #         coverage
+            #         ;
+            #     }
+            #   );
+            # })
             (final: prev: {
               inherit (pkgs-unoptimized)
                 gsl