diff --git a/nixos/modules/services/web-apps/miniflux.nix b/nixos/modules/services/web-apps/miniflux.nix
index 641c9be85d8cb3..94beef2d29bbe7 100644
--- a/nixos/modules/services/web-apps/miniflux.nix
+++ b/nixos/modules/services/web-apps/miniflux.nix
@@ -40,7 +40,7 @@ in
       };
 
       adminCredentialsFile = mkOption  {
-        type = types.path;
+        type = types.secretFile;
         description = ''
           File containing the ADMIN_USERNAME and
           ADMIN_PASSWORD (length >= 6) in the format of
diff --git a/nixos/tests/miniflux.nix b/nixos/tests/miniflux.nix
index d905aea048a3ae..40060be8c599fe 100644
--- a/nixos/tests/miniflux.nix
+++ b/nixos/tests/miniflux.nix
@@ -7,14 +7,14 @@ let
   defaultPort = 8080;
   defaultUsername = "admin";
   defaultPassword = "password";
-  adminCredentialsFile = pkgs.writeText "admin-credentials" ''
+  adminCredentialsFile = lib.types.secretFile.makeWorldReadable (pkgs.writeText "admin-credentials" ''
             ADMIN_USERNAME=${defaultUsername}
             ADMIN_PASSWORD=${defaultPassword}
-          '';
-  customAdminCredentialsFile = pkgs.writeText "admin-credentials" ''
+          '');
+  customAdminCredentialsFile = lib.types.secretFile.makeWorldReadable (pkgs.writeText "admin-credentials" ''
             ADMIN_USERNAME=${username}
             ADMIN_PASSWORD=${password}
-          '';
+          '');
 
 in
 with lib;