diff --git a/pkgs/os-specific/linux/kernel/linux-testing-bcachefs.nix b/pkgs/os-specific/linux/kernel/linux-testing-bcachefs.nix
index 378461f217e8..fa5729baf73a 100644
--- a/pkgs/os-specific/linux/kernel/linux-testing-bcachefs.nix
+++ b/pkgs/os-specific/linux/kernel/linux-testing-bcachefs.nix
@@ -1,6 +1,7 @@
 { lib, buildPackages, fetchFromGitHub, fetchpatch, perl, buildLinux, ... } @ args:
 
 buildLinux (args // {
+  # NOTE: bcachefs-tools should be updated simultaneously to preserve compatibility
   version = "5.13.0-2021.10.01";
   modDirVersion = "5.13.0";