3 files changed, 6 insertions, 7 deletions
diff --git a/nixos/modules/system/boot/loader/grub/grub.nix b/nixos/modules/system/boot/loader/grub/grub.nix
index 121d7e88e74d..5c0a07fb5127 100644
--- a/nixos/modules/system/boot/loader/grub/grub.nix
+++ b/nixos/modules/system/boot/loader/grub/grub.nix
@@ -33,7 +33,7 @@ let
     then realGrub.override { efiSupport = cfg.efiSupport; }
     else null;
 
-  f = x: if x == null then "" else "" + x;
+  f = x: optionalString (x != null) ("" + x);
 
   grubConfig = args:
     let
@@ -52,7 +52,7 @@ let
       fullName = lib.getName realGrub;
       fullVersion = lib.getVersion realGrub;
       grubEfi = f grubEfi;
-      grubTargetEfi = if cfg.efiSupport && (cfg.version == 2) then f (grubEfi.grubTarget or "") else "";
+      grubTargetEfi = optionalString (cfg.efiSupport && (cfg.version == 2)) (f (grubEfi.grubTarget or ""));
       bootPath = args.path;
       storePath = config.boot.loader.grub.storePath;
       bootloaderId = if args.efiBootloaderId == null then "${config.system.nixos.distroName}${efiSysMountPoint'}" else args.efiBootloaderId;
diff --git a/nixos/modules/system/boot/loader/systemd-boot/systemd-boot.nix b/nixos/modules/system/boot/loader/systemd-boot/systemd-boot.nix
index 757dc080d4b6..8a3e89e5888b 100644
--- a/nixos/modules/system/boot/loader/systemd-boot/systemd-boot.nix
+++ b/nixos/modules/system/boot/loader/systemd-boot/systemd-boot.nix
@@ -20,7 +20,7 @@ let
 
     nix = config.nix.package.out;
 
-    timeout = if config.boot.loader.timeout != null then config.boot.loader.timeout else "";
+    timeout = optionalString (config.boot.loader.timeout != null) config.boot.loader.timeout;
 
     editor = if cfg.editor then "True" else "False";
 
@@ -32,9 +32,9 @@ let
 
     inherit (config.system.nixos) distroName;
 
-    memtest86 = if cfg.memtest86.enable then pkgs.memtest86-efi else "";
+    memtest86 = optionalString cfg.memtest86.enable pkgs.memtest86-efi;
 
-    netbootxyz = if cfg.netbootxyz.enable then pkgs.netbootxyz-efi else "";
+    netbootxyz = optionalString cfg.netbootxyz.enable pkgs.netbootxyz-efi;
 
     copyExtraFiles = pkgs.writeShellScript "copy-extra-files" ''
       empty_file=$(${pkgs.coreutils}/bin/mktemp)
diff --git a/nixos/modules/system/boot/luksroot.nix b/nixos/modules/system/boot/luksroot.nix
index 8954c90812f9..b8f36538e70f 100644
--- a/nixos/modules/system/boot/luksroot.nix
+++ b/nixos/modules/system/boot/luksroot.nix
@@ -1024,13 +1024,12 @@ in
         copy_bin_and_libs ${pkgs.gnupg}/libexec/scdaemon
 
         ${concatMapStringsSep "\n" (x:
-          if x.gpgCard != null then
+          optionalString (x.gpgCard != null)
             ''
               mkdir -p $out/secrets/gpg-keys/${x.device}
               cp -a ${x.gpgCard.encryptedPass} $out/secrets/gpg-keys/${x.device}/cryptkey.gpg
               cp -a ${x.gpgCard.publicKey} $out/secrets/gpg-keys/${x.device}/pubkey.asc
             ''
-          else ""
           ) (attrValues luks.devices)
         }
       ''}