diff --git a/flake.nix b/flake.nix
index 78524a94..a9d99ca9 100644
--- a/flake.nix
+++ b/flake.nix
@@ -34,6 +34,9 @@
     # which represents the GitHub repository URL + branch/commit-id/tag.
 
     # Official NixOS package source, using nixos's unstable branch by default
+    # Find git commit hash with build status here(3 jobs per day):
+    # https://hydra.nixos.org/jobset/nixpkgs/unstable
+    # update via nix flake update nixpkgs --override-input nixpkgs github:NixOS/nixpkgs/<commit-hash>
     nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
     nixpkgs-stable.url = "github:nixos/nixpkgs/nixos-25.11";
     # revert mesa to 25.2.6