diff --git a/nixos/modules/security/acme.nix b/nixos/modules/security/acme.nix
index 211199d148dc..4c7f0ee657ce 100644
--- a/nixos/modules/security/acme.nix
+++ b/nixos/modules/security/acme.nix
@@ -352,7 +352,7 @@ in
                             cp -p ${spath}/certificates/${keyName}.key key.pem
                             cp -p ${spath}/certificates/${keyName}.crt fullchain.pem
                             cp -p ${spath}/certificates/${keyName}.issuer.crt chain.pem
-                            ln -s fullchain.pem cert.pem
+                            ln -sf fullchain.pem cert.pem
                             cat key.pem fullchain.pem > full.pem
                             chmod ${rights} *.pem
                             chown '${data.user}:${data.group}' *.pem