bump nixpkgs

tests/flake.lock

@@ -2,11 +2,11 @@
   "nodes": {
     "nixos-stable": {
       "locked": {
-        "lastModified": 1755274400,
-        "narHash": "sha256-rTInmnp/xYrfcMZyFMH3kc8oko5zYfxsowaLv1LVobY=",
+        "lastModified": 1761597516,
+        "narHash": "sha256-wxX7u6D2rpkJLWkZ2E932SIvDJW8+ON/0Yy8+a5vsDU=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "ad7196ae55c295f53a7d1ec39e4a06d922f3b899",
+        "rev": "daf6dc47aa4b44791372d6139ab7b25269184d55",
         "type": "github"
       },
       "original": {
@@ -18,11 +18,11 @@
     },
     "nixos-unstable-small": {
       "locked": {
-        "lastModified": 1755375481,
-        "narHash": "sha256-43PgCQFgFD1nM/7dncytV0c5heNHe/gXrEud18ZWcZU=",
+        "lastModified": 1761789293,
+        "narHash": "sha256-zwQKLaUgHSpY6SvB/MDgPYRPomWAmbkS3Xfo6JvFVOA=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "35f1742e4f1470817ff8203185e2ce0359947f12",
+        "rev": "8d42228a0de7c23b012e2f7dd963425a372e1b0e",
         "type": "github"
       },
       "original": {
@@ -46,11 +46,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1750931469,
-        "narHash": "sha256-0IEdQB1nS+uViQw4k3VGUXntjkDp7aAlqcxdewb/hAc=",
+        "lastModified": 1761311587,
+        "narHash": "sha256-Msq86cR5SjozQGCnC6H8C+0cD4rnx91BPltZ9KK613Y=",
         "owner": "numtide",
         "repo": "treefmt-nix",
-        "rev": "ac8e6f32e11e9c7f153823abc3ab007f2a65d3e1",
+        "rev": "2eddae033e4e74bf581c2d1dfa101f9033dbd2dc",
         "type": "github"
       },
       "original": {

tests/run.py

@@ -69,6 +69,7 @@ def run_eval_test(gcroot_dir: Path, jobs: int) -> list[str]:
     failed_profiles = []
     cmd = [
         "nix-eval-jobs",
+        "--no-instantiate",
         "--extra-experimental-features", "flakes",
         "--option", "eval-cache", "false",
         "--gc-roots-dir",