diff --git a/pkgs/shells/zsh/default.nix b/pkgs/shells/zsh/default.nix
index 3a5a83ad1f8c..18fa69c60427 100644
--- a/pkgs/shells/zsh/default.nix
+++ b/pkgs/shells/zsh/default.nix
@@ -71,7 +71,7 @@ if test -e /etc/NIXOS; then
   else
     emulate bash
     alias shopt=false
-    if [ -z "$__NIXOS_SET_ENVIRONMENT_DONE" ]; then
+    if [ -z "\$__NIXOS_SET_ENVIRONMENT_DONE" ]; then
       . /etc/set-environment
     fi
     unalias shopt