diff --git a/flake.nix b/flake.nix
index 99a53c1..3da190a 100644
--- a/flake.nix
+++ b/flake.nix
@@ -185,6 +185,8 @@
           buildInputs = [ zynqpkgs.mkbootimage ];
         }
         ''
+          # Do not use "long" paths in boot.bif, because embedded developers
+          # can't write software (mkbootimage will segfault).        
           bifdir=`mktemp -d`
           cd $bifdir
           ln -s ${szl}/szl.elf szl.elf