diff --git a/BREAKING_CHANGES.md b/BREAKING_CHANGES.md
new file mode 100644
index 0000000..78a41fc
--- /dev/null
+++ b/BREAKING_CHANGES.md
@@ -0,0 +1,3 @@
+2023-02-14 6d630b8
+
+btrfs, btrfs_subvol filesystem and lvm_lv extraArgs are now lists
diff --git a/default.nix b/default.nix
index 33473bf..c352481 100644
--- a/default.nix
+++ b/default.nix
@@ -1,5 +1,6 @@
 { lib ? import <nixpkgs/lib>
 , rootMountPoint ? "/mnt"
+, checked ? false
 }:
 let
   types = import ./types { inherit lib rootMountPoint; };
@@ -18,33 +19,27 @@ in
 {
   types = types;
   create = cfg: types.diskoLib.create (eval cfg).config.devices;
-  createScript = cfg: pkgs: pkgs.writeScript "disko-create" ''
-    #!/usr/bin/env bash
+  createScript = cfg: pkgs: (types.diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko-create" ''
     export PATH=${lib.makeBinPath (types.diskoLib.packages (eval cfg).config.devices pkgs)}:$PATH
     ${types.diskoLib.create (eval cfg).config.devices}
   '';
-  createScriptNoDeps = cfg: pkgs: pkgs.writeScript "disko-create" ''
-    #!/usr/bin/env bash
+  createScriptNoDeps = cfg: pkgs: (types.diskoLib.writeCheckedBash { inherit pkgs checked; noDeps = true; }) "disko-create" ''
     ${types.diskoLib.create (eval cfg).config.devices}
   '';
   mount = cfg: types.diskoLib.mount (eval cfg).config.devices;
-  mountScript = cfg: pkgs: pkgs.writeScript "disko-mount" ''
-    #!/usr/bin/env bash
+  mountScript = cfg: pkgs: (types.diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko-mount" ''
     export PATH=${lib.makeBinPath (types.diskoLib.packages (eval cfg).config.devices pkgs)}:$PATH
     ${types.diskoLib.mount (eval cfg).config.devices}
   '';
-  mountScriptNoDeps = cfg: pkgs: pkgs.writeScript "disko-mount" ''
-    #!/usr/bin/env bash
+  mountScriptNoDeps = cfg: pkgs: (types.diskoLib.writeCheckedBash { inherit pkgs checked; noDeps = true; }) "disko-mount" ''
     ${types.diskoLib.mount (eval cfg).config.devices}
   '';
   zapCreateMount = cfg: types.diskoLib.zapCreateMount (eval cfg).config.devices;
-  zapCreateMountScript = cfg: pkgs: pkgs.writeScript "disko-zap-create-mount" ''
-    #!/usr/bin/env bash
+  zapCreateMountScript = cfg: pkgs: (types.diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko-zap-create-mount" ''
     export PATH=${lib.makeBinPath (types.diskoLib.packages (eval cfg).config.devices pkgs)}:$PATH
     ${types.diskoLib.zapCreateMount (eval cfg).config.devices}
   '';
-  zapCreateMountScriptNoDeps = cfg: pkgs: pkgs.writeScript "disko-zap-create-mount" ''
-    #!/usr/bin/env bash
+  zapCreateMountScriptNoDeps = cfg: pkgs: (types.diskoLib.writeCheckedBash { inherit pkgs checked; noDeps = true; }) "disko-zap-create-mount" ''
     ${types.diskoLib.zapCreateMount (eval cfg).config.devices}
   '';
   config = cfg: { imports = types.diskoLib.config (eval cfg).config.devices; };
diff --git a/example/btrfs-subvolumes.nix b/example/btrfs-subvolumes.nix
index a6d8088..a574570 100644
--- a/example/btrfs-subvolumes.nix
+++ b/example/btrfs-subvolumes.nix
@@ -27,7 +27,7 @@
             end = "100%";
             content = {
               type = "btrfs";
-              extraArgs = "-f"; # Override existing partition
+              extraArgs = [ "-f" ]; # Override existing partition
               subvolumes = {
                 # Subvolume name is different from mountpoint
                 "/rootfs" = {
diff --git a/module.nix b/module.nix
index 820d985..afdd315 100644
--- a/module.nix
+++ b/module.nix
@@ -5,6 +5,7 @@ let
     rootMountPoint = config.disko.rootMountPoint;
   };
   cfg = config.disko;
+  checked = cfg.checkScripts;
 in
 {
   options.disko = {
@@ -27,26 +28,32 @@ in
       type = lib.types.bool;
       default = true;
     };
+    checkScripts = lib.mkOption {
+      description = ''
+        Whether to run shellcheck on script outputs
+      '';
+      type = lib.types.bool;
+      default = false;
+    };
   };
   config = lib.mkIf (cfg.devices.disk != { }) {
-    system.build.formatScript = pkgs.writers.writeBash "disko-create" ''
+    system.build.formatScript = (types.diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko-create" ''
       export PATH=${lib.makeBinPath (types.diskoLib.packages cfg.devices pkgs)}:$PATH
       ${types.diskoLib.create cfg.devices}
     '';
 
-    system.build.mountScript = pkgs.writers.writeBash "disko-mount" ''
+    system.build.mountScript = (types.diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko-mount" ''
       export PATH=${lib.makeBinPath (types.diskoLib.packages cfg.devices pkgs)}:$PATH
       ${types.diskoLib.mount cfg.devices}
     '';
 
-    system.build.disko = pkgs.writers.writeBash "disko" ''
+    system.build.disko = (types.diskoLib.writeCheckedBash { inherit pkgs checked; }) "disko" ''
       export PATH=${lib.makeBinPath (types.diskoLib.packages cfg.devices pkgs)}:$PATH
       ${types.diskoLib.zapCreateMount cfg.devices}
     '';
 
     # This is useful to skip copying executables uploading a script to an in-memory installer
-    system.build.diskoNoDeps = pkgs.writeScript "disko" ''
-      #!/usr/bin/env bash
+    system.build.diskoNoDeps = (types.diskoLib.writeCheckedBash { inherit pkgs checked; noDeps = true; }) "disko" ''
       ${types.diskoLib.zapCreateMount cfg.devices}
     '';
 
diff --git a/tests/default.nix b/tests/default.nix
index 1efc16c..3a9e072 100644
--- a/tests/default.nix
+++ b/tests/default.nix
@@ -11,8 +11,8 @@ let
       disko-config = import configFile;
     in
     {
-      "${name}-tsp-create" = pkgs.writeScript "create" ((pkgs.callPackage ../. { }).create disko-config);
-      "${name}-tsp-mount" = pkgs.writeScript "mount" ((pkgs.callPackage ../. { }).mount disko-config);
+      "${name}-tsp-create" = (pkgs.callPackage ../. { checked = true; }).createScript disko-config pkgs;
+      "${name}-tsp-mount" = (pkgs.callPackage ../. { checked = true; }).mountScript disko-config pkgs;
     };
 
   allTestFilenames =
diff --git a/tests/lib.nix b/tests/lib.nix
index 43b6607..c3d8957 100644
--- a/tests/lib.nix
+++ b/tests/lib.nix
@@ -24,10 +24,11 @@
           inherit (pkgs) system;
         };
       disks = [ "/dev/vda" "/dev/vdb" "/dev/vdc" "/dev/vdd" "/dev/vde" "/dev/vdf" ];
-      tsp-create = pkgs.writeScript "create" ((pkgs.callPackage ../. { }).create (import disko-config { disks = builtins.tail disks; inherit lib; }));
-      tsp-mount = pkgs.writeScript "mount" ((pkgs.callPackage ../. { }).mount (import disko-config { disks = builtins.tail disks; inherit lib; }));
-      tsp-config = (pkgs.callPackage ../. { }).config (import disko-config { inherit disks; inherit lib; });
-      tsp-disko = pkgs.writeScript "disko" ((pkgs.callPackage ../. { }).zapCreateMount (import disko-config { disks = builtins.tail disks; inherit lib; }));
+      tsp-generator = pkgs.callPackage ../. { checked = true; };
+      tsp-create = (tsp-generator.createScript (import disko-config { disks = builtins.tail disks; inherit lib; })) pkgs;
+      tsp-mount = (tsp-generator.mountScript (import disko-config { disks = builtins.tail disks; inherit lib; })) pkgs;
+      tsp-disko = (tsp-generator.zapCreateMountScript (import disko-config { disks = builtins.tail disks; inherit lib; })) pkgs;
+      tsp-config = tsp-generator.config (import disko-config { inherit disks; inherit lib; });
       num-disks = builtins.length (lib.attrNames (import disko-config { inherit lib; }).disk);
       installed-system = { modulesPath, ... }: {
         imports = [
@@ -78,14 +79,15 @@
             imports = [ ../module.nix ];
             disko = {
               enableConfig = false;
+              checkScripts = true;
               devices = import disko-config { disks = builtins.tail disks; inherit lib; };
             };
           })
           (lib.optionalAttrs (testMode == "cli") {
             imports = [ (modulesPath + "/installer/cd-dvd/channel.nix") ];
             system.extraDependencies = [
-              ((pkgs.callPackage ../. { }).createScript (import disko-config { disks = builtins.tail disks; inherit lib; }) pkgs)
-              ((pkgs.callPackage ../. { }).mountScript (import disko-config { disks = builtins.tail disks; inherit lib; }) pkgs)
+              ((pkgs.callPackage ../. { checked = true; }).createScript (import disko-config { disks = builtins.tail disks; inherit lib; }) pkgs)
+              ((pkgs.callPackage ../. { checked = true; }).mountScript (import disko-config { disks = builtins.tail disks; inherit lib; }) pkgs)
             ];
           })
           (modulesPath + "/profiles/base.nix")
diff --git a/types/btrfs.nix b/types/btrfs.nix
index 9473db7..ce212cd 100644
--- a/types/btrfs.nix
+++ b/types/btrfs.nix
@@ -7,9 +7,9 @@
       description = "Type";
     };
     extraArgs = lib.mkOption {
-      type = lib.types.str;
-      default = "";
-      description = "Arguments to pass to BTRFS";
+      type = lib.types.listOf lib.types.str;
+      default = [ ];
+      description = "Extra arguments";
     };
     mountOptions = lib.mkOption {
       type = lib.types.listOf lib.types.str;
@@ -37,7 +37,7 @@
     _create = diskoLib.mkCreateOption {
       inherit config options;
       default = { dev }: ''
-        mkfs.btrfs ${dev} ${config.extraArgs}
+        mkfs.btrfs ${dev} ${toString config.extraArgs}
         ${lib.concatMapStrings (subvol: subvol._create { inherit dev; }) (lib.attrValues config.subvolumes)}
       '';
     };
diff --git a/types/btrfs_subvol.nix b/types/btrfs_subvol.nix
index 699d3e8..caba3fe 100644
--- a/types/btrfs_subvol.nix
+++ b/types/btrfs_subvol.nix
@@ -13,9 +13,9 @@
       description = "Type";
     };
     extraArgs = lib.mkOption {
-      type = lib.types.str;
-      default = "";
-      description = "Extra arguments to pass";
+      type = lib.types.listOf lib.types.str;
+      default = [ ];
+      description = "Extra arguments";
     };
     mountOptions = lib.mkOption {
       type = lib.types.listOf lib.types.str;
@@ -41,7 +41,7 @@
         (
           mount ${dev} "$MNTPOINT" -o subvol=/
           trap 'umount $MNTPOINT; rm -rf $MNTPOINT' EXIT
-          btrfs subvolume create "$MNTPOINT"/${config.name} ${config.extraArgs}
+          btrfs subvolume create "$MNTPOINT"/${config.name} ${toString config.extraArgs}
         )
       '';
     };
diff --git a/types/default.nix b/types/default.nix
index 2c967f6..f0e1909 100644
--- a/types/default.nix
+++ b/types/default.nix
@@ -193,6 +193,15 @@ rec {
         description = "Mount script";
       };
 
+    /* Writer for optionally checking bash scripts before writing them to the store
+
+       writeCheckedBash :: AttrSet -> str -> str -> derivation
+    */
+    writeCheckedBash = { pkgs, checked ? false, noDeps ? false }: pkgs.writers.makeScriptWriter {
+      interpreter = if noDeps then "/usr/bin/env bash" else "${pkgs.bash}/bin/bash";
+      check = lib.optionalString checked "${pkgs.shellcheck}/bin/shellcheck -e SC2034";
+    };
+
 
     /* Takes a disko device specification, returns an attrset with metadata
 
@@ -243,6 +252,7 @@ rec {
       set -efux
       umount -Rv "${rootMountPoint}" || :
 
+      # shellcheck disable=SC2043
       for dev in ${toString (lib.catAttrs "device" (lib.attrValues devices.disk))}; do
         ${../disk-deactivate}/disk-deactivate "$dev" | bash -x
       done
diff --git a/types/filesystem.nix b/types/filesystem.nix
index c9a3319..93d0cac 100644
--- a/types/filesystem.nix
+++ b/types/filesystem.nix
@@ -7,9 +7,9 @@
       description = "Type";
     };
     extraArgs = lib.mkOption {
-      type = lib.types.str;
-      default = "";
-      description = "Arguments to pass";
+      type = lib.types.listOf lib.types.str;
+      default = [ ];
+      description = "Extra arguments";
     };
     mountOptions = lib.mkOption {
       type = lib.types.listOf lib.types.str;
@@ -35,7 +35,7 @@
       inherit config options;
       default = { dev }: ''
         mkfs.${config.format} \
-          ${config.extraArgs} \
+          ${toString config.extraArgs} \
           ${dev}
       '';
     };
diff --git a/types/lvm_lv.nix b/types/lvm_lv.nix
index 7ffa268..d2df6fc 100644
--- a/types/lvm_lv.nix
+++ b/types/lvm_lv.nix
@@ -22,8 +22,8 @@
       description = "LVM type";
     };
     extraArgs = lib.mkOption {
-      type = lib.types.str;
-      default = "";
+      type = lib.types.listOf lib.types.str;
+      default = [ ];
       description = "Extra arguments";
     };
     content = diskoLib.partitionType;
@@ -43,7 +43,7 @@
           ${if lib.hasInfix "%" config.size then "-l" else "-L"} ${config.size} \
           -n ${config.name} \
           ${lib.optionalString (config.lvm_type != null) "--type=${config.lvm_type}"} \
-          ${config.extraArgs} \
+          ${toString config.extraArgs} \
           ${vg}
         ${lib.optionalString (config.content != null) (config.content._create {dev = "/dev/${vg}/${config.name}";})}
       '';
diff --git a/types/lvm_pv.nix b/types/lvm_pv.nix
index 03a95c7..1bf1c10 100644
--- a/types/lvm_pv.nix
+++ b/types/lvm_pv.nix
@@ -23,7 +23,7 @@
       inherit config options;
       default = { dev }: ''
         pvcreate ${dev}
-        echo "${dev}" >> $disko_devices_dir/lvm_${config.vg}
+        echo "${dev}" >> "$disko_devices_dir"/lvm_${config.vg}
       '';
     };
     _mount = diskoLib.mkMountOption {
diff --git a/types/lvm_vg.nix b/types/lvm_vg.nix
index ba313e1..ac7c2fa 100644
--- a/types/lvm_vg.nix
+++ b/types/lvm_vg.nix
@@ -27,7 +27,9 @@
     _create = diskoLib.mkCreateOption {
       inherit config options;
       default = _: ''
-        vgcreate ${config.name} $(tr '\n' ' ' < $disko_devices_dir/lvm_${config.name})
+        readarray -t lvm_devices < <(cat "$disko_devices_dir"/lvm_${config.name})
+        vgcreate ${config.name} \
+        "''${lvm_devices[@]}"
         ${lib.concatMapStrings (lv: lv._create {vg = config.name; }) (lib.attrValues config.lvs)}
       '';
     };
diff --git a/types/mdadm.nix b/types/mdadm.nix
index d2b3937..5d1f043 100644
--- a/types/mdadm.nix
+++ b/types/mdadm.nix
@@ -34,13 +34,14 @@
     _create = diskoLib.mkCreateOption {
       inherit config options;
       default = _: ''
+        readarray -t disk_devices < <(cat "$disko_devices_dir"/raid_${config.name})
         echo 'y' | mdadm --create /dev/md/${config.name} \
           --level=${toString config.level} \
-          --raid-devices=$(wc -l $disko_devices_dir/raid_${config.name} | cut -f 1 -d " ") \
+          --raid-devices="$(wc -l "$disko_devices_dir"/raid_${config.name} | cut -f 1 -d " ")" \
           --metadata=${config.metadata} \
           --force \
           --homehost=any \
-          $(tr '\n' ' ' < $disko_devices_dir/raid_${config.name})
+          "''${disk_devices[@]}"
         udevadm trigger --subsystem-match=block; udevadm settle
         ${lib.optionalString (config.content != null) (config.content._create {dev = "/dev/md/${config.name}";})}
       '';
diff --git a/types/mdraid.nix b/types/mdraid.nix
index 6eb24bc..52b7b03 100644
--- a/types/mdraid.nix
+++ b/types/mdraid.nix
@@ -23,7 +23,7 @@
     _create = diskoLib.mkCreateOption {
       inherit config options;
       default = { dev }: ''
-        echo "${dev}" >> $disko_devices_dir/raid_${config.name}
+        echo "${dev}" >> "$disko_devices_dir"/raid_${config.name}
       '';
     };
     _mount = diskoLib.mkMountOption {
diff --git a/types/zfs.nix b/types/zfs.nix
index b30ad44..26e53ab 100644
--- a/types/zfs.nix
+++ b/types/zfs.nix
@@ -22,7 +22,7 @@
     _create = diskoLib.mkCreateOption {
       inherit config options;
       default = { dev }: ''
-        echo "${dev}" >> $disko_devices_dir/zfs_${config.pool}
+        echo "${dev}" >> "$disko_devices_dir"/zfs_${config.pool}
       '';
     };
     _mount = diskoLib.mkMountOption {
diff --git a/types/zpool.nix b/types/zpool.nix
index de2b70d..0a7e66a 100644
--- a/types/zpool.nix
+++ b/types/zpool.nix
@@ -52,11 +52,12 @@
     _create = diskoLib.mkCreateOption {
       inherit config options;
       default = _: ''
+        readarray -t zfs_devices < <(cat "$disko_devices_dir"/zfs_${config.name})
         zpool create ${config.name} \
           ${config.mode} \
           ${lib.concatStringsSep " " (lib.mapAttrsToList (n: v: "-o ${n}=${v}") config.options)} \
           ${lib.concatStringsSep " " (lib.mapAttrsToList (n: v: "-O ${n}=${v}") config.rootFsOptions)} \
-          $(tr '\n' ' ' < $disko_devices_dir/zfs_${config.name})
+          "''${zfs_devices[@]}"
         ${lib.concatMapStrings (dataset: dataset._create {zpool = config.name;}) (lib.attrValues config.datasets)}
       '';
     };