diff --git a/doc/manual/src/hacking.md b/doc/manual/src/hacking.md
index 9d98b00c..72a74c82 100644
--- a/doc/manual/src/hacking.md
+++ b/doc/manual/src/hacking.md
@@ -92,7 +92,7 @@ On NixOS:
 
 ```nix
 {
-  nix.trustedUsers = [ "YOURUSER" ];
+  nix.settings.trusted-users = [ "YOURUSER" ];
 }
 ```