diff --git a/pkgs/tools/package-management/nix/default.nix b/pkgs/tools/package-management/nix/default.nix
index f1db0c60eee7..01335fcc7426 100644
--- a/pkgs/tools/package-management/nix/default.nix
+++ b/pkgs/tools/package-management/nix/default.nix
@@ -215,7 +215,7 @@ in lib.makeExtensible (self: ({
 
   stable = self.nix_2_17;
 
-  unstable = self.stable;
+  unstable = self.nix_2_18;
 } // lib.optionalAttrs config.allowAliases {
   nix_2_4 = throw "nixVersions.nix_2_4 has been removed";