diff --git a/flake.lock b/flake.lock
index 3acbb514fc..3d31cd249f 100644
--- a/flake.lock
+++ b/flake.lock
@@ -20,11 +20,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1728538411,
-        "narHash": "sha256-f0SBJz1eZ2yOuKUr5CA9BHULGXVSn6miBuUWdTyhUhU=",
+        "lastModified": 1730958623,
+        "narHash": "sha256-JwQZIGSYnRNOgDDoIgqKITrPVil+RMWHsZH1eE1VGN0=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "b69de56fac8c2b6f8fd27f2eca01dcda8e0a4221",
+        "rev": "85f7e662eda4fa3a995556527c87b2524b691933",
         "type": "github"
       },
       "original": {
@@ -46,11 +46,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1729304879,
-        "narHash": "sha256-H7KGGJUU9BcDNnfXiATBGgs6FJKWQdfftNJS+/v2aMU=",
+        "lastModified": 1731292155,
+        "narHash": "sha256-fYVoUUtSadbOrH0z0epVQDsStBDS/S/fAK//0ECQAAI=",
         "owner": "oxalica",
         "repo": "rust-overlay",
-        "rev": "b259ef799b5ac014604da71ecd92d4a52603ed2d",
+        "rev": "7c4cd99ed7604b79e8cb721099ac99c66f656b3a",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index 110eb81bd6..d478c3bbfb 100644
--- a/flake.nix
+++ b/flake.nix
@@ -77,6 +77,14 @@
           buildFeatures = [ "packaging" ];
           cargoBuildFlags = [ "--bin" "jj" ]; # don't build and install the fake editors
           useNextest = true;
+
+          checkFlags = [
+            # https://github.com/martinvonz/jj/issues/4784
+            # seems to fail reliably under Nix/nix-shell only, but otherwise
+            # is an unknown anomaly?
+            "--skip" "test_shallow_commits_lack_parents"
+          ];
+          
           src = filterSrc ./. [
             ".*\\.nix$"
             "^.jj/"