diff --git a/hosts/nixos/merope/services/media/calibre-web.nix b/hosts/nixos/merope/services/media/calibre-web.nix
index e3dc206c..9cdcb8d0 100644
--- a/hosts/nixos/merope/services/media/calibre-web.nix
+++ b/hosts/nixos/merope/services/media/calibre-web.nix
@@ -43,6 +43,7 @@
     calibre-web.serviceConfig = {
       CPUWeight = 50;
       IOWeight = 50;
+      UMask = "0002";
     };
   };