diff --git a/common.nix b/common.nix
index df9f8e5..dcbd329 100644
--- a/common.nix
+++ b/common.nix
@@ -29,6 +29,9 @@
   nix.gc.options = "--delete-older-than 8d";
   nix.settings = {
     fallback = true;
+    # This cache is backed by Misaki's garbage-collected Nix store. Avoid
+    # retaining narinfo for the default 30 days after its NAR is collected.
+    narinfo-cache-positive-ttl = 86400;
     substituters = [
       "https://tranquil.cachix.org"
       "https://cache.ngp.computer"
diff --git a/flake.lock b/flake.lock
index ea45bb8..ad72935 100644
--- a/flake.lock
+++ b/flake.lock
@@ -638,11 +638,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1785207637,
-        "narHash": "sha256-FlaOYL3HRfH4fPg0fYu71fJINnbcnWaz0KPVGfDgk4I=",
+        "lastModified": 1785251706,
+        "narHash": "sha256-5p/SL9RSApOz6AYZSLYgdtm5WC6MJidqJ7lDx0HeTWE=",
         "owner": "chiefnoah",
         "repo": "ngp-nur",
-        "rev": "1d7c6e1af87a70a2f54c470bf55958742ffd46f7",
+        "rev": "5166ba82ce0cbd2a898da6985672a2043d3d9f1d",
         "type": "github"
       },
       "original": {
diff --git a/mkfile b/mkfile
index 8d50b9c..a6b5ffd 100644
--- a/mkfile
+++ b/mkfile
@@ -9,8 +9,7 @@ default:V:
 
 rebuild:V:
     git pull --rebase
-    sudo nixos-rebuild switch --flake $gitroot
-    mk clean
+    exec sudo nixos-rebuild switch --flake $gitroot
 
 edge:V:
     exec nixos-rebuild switch --flake $gitroot'#edge' --target-host edge