diff --git a/systemd-hardening-in-NixOS/article.md b/systemd-hardening-in-NixOS/article.md
index 5f712fe..5c6d501 100644
--- a/systemd-hardening-in-NixOS/article.md
+++ b/systemd-hardening-in-NixOS/article.md
@@ -32,7 +32,7 @@ You can find more information about such options [online](https://search.nixos.o
 In a nutshell, configuring systemd options for services on NixOS typically boils down to these steps:
 
 1. edit `systemd.services.*` options in `configuration.nix` or in other imported nix files;
-2. run `sudo nixos-rebuild test` to apply new configuration just for now or `sudo nixos-rebuild switch` to apply changes permanently;
+2. run `sudo nixos-rebuild test` to apply new configuration just for the current OS boot or `sudo nixos-rebuild switch` to apply changes permanently (additionally add `--flake /etc/nixos` for flakes);
 3. evaluate `systemd` service operation (we will elaborate on this further);
 4. return to step 1 or finish.