diff --git a/example/zfs-with-vdevs.nix b/example/zfs-with-vdevs.nix
index 96750fd..a61680a 100644
--- a/example/zfs-with-vdevs.nix
+++ b/example/zfs-with-vdevs.nix
@@ -93,8 +93,6 @@
             cache = [ "cache" ];
           };
         };
-        # Workaround: cannot import 'zroot': I/O error in disko tests
-        options.cachefile = "none";
 
         rootFsOptions = {
           compression = "zstd";
diff --git a/lib/tests.nix b/lib/tests.nix
index e2e8f60..0aff420 100644
--- a/lib/tests.nix
+++ b/lib/tests.nix
@@ -86,7 +86,7 @@ let
         tsp-config = tsp-generator.config testConfigBooted;
         num-disks = builtins.length (lib.attrNames testConfigBooted.disko.devices.disk);
 
-        installed-system = { ... }: {
+        installed-system = { config, ... }: {
           imports = [
             (lib.optionalAttrs (testMode == "direct") tsp-config)
             (lib.optionalAttrs (testMode == "module") {
@@ -101,7 +101,8 @@ let
           # config for tests to make them run faster or work at all
           documentation.enable = false;
           hardware.enableAllFirmware = lib.mkForce false;
-          boot.initrd.preDeviceCommands = ''
+          # FIXME: we don't have an systemd in stage-1 equialvent for this
+          boot.initrd.preDeviceCommands = lib.mkIf (!config.boot.initrd.systemd.enable) ''
             echo -n 'secretsecret' > /tmp/secret.key
           '';
           boot.consoleLogLevel = lib.mkForce 100;
diff --git a/lib/types/zpool.nix b/lib/types/zpool.nix
index 24d155a..e534db3 100644
--- a/lib/types/zpool.nix
+++ b/lib/types/zpool.nix
@@ -79,7 +79,7 @@ in
                     };
                     cache = lib.mkOption {
                       type = lib.types.listOf lib.types.str;
-                      default = null;
+                      default = [];
                       description = ''
                         A dedicated zfs cache device (L2ARC). See
                         https://openzfs.github.io/openzfs-docs/man/master/7/zpoolconcepts.7.html#Cache_Devices
diff --git a/tests/zfs-with-vdevs.nix b/tests/zfs-with-vdevs.nix
index dbca4fc..da301a0 100644
--- a/tests/zfs-with-vdevs.nix
+++ b/tests/zfs-with-vdevs.nix
@@ -8,6 +8,15 @@ diskoLib.testLib.makeDiskoTest {
   extraInstallerConfig.networking.hostId = "8425e349";
   extraSystemConfig = {
     networking.hostId = "8425e349";
+    # It looks like the 60s of NixOS is sometimes not enough for our virtio-based zpool.
+    # This fixes the flakeiness of the test.
+    boot.initrd.postResumeCommands = ''
+      for i in $(seq 1 120); do
+        if zpool list | grep -q zroot || zpool import -N zroot; then
+          break
+        fi
+      done
+    '';
   };
   extraTestScript = ''
     def assert_property(ds, property, expected_value):