diff --git a/crates/examples/root-task/serial-device/src/main.rs b/crates/examples/root-task/serial-device/src/main.rs
index 4675a3f62..cbdba1f3e 100644
--- a/crates/examples/root-task/serial-device/src/main.rs
+++ b/crates/examples/root-task/serial-device/src/main.rs
@@ -128,11 +128,11 @@ fn main(bootinfo: &sel4::BootInfoPtr) -> sel4::Result<Never> {
 
         irq_notification_cap.wait();
 
-        let c = serial_device.get_char().unwrap();
-
-        serial_device.put_char(b'[');
-        serial_device.put_char(c);
-        serial_device.put_char(b']');
+        while let Some(c) = serial_device.get_char() {
+            serial_device.put_char(b'[');
+            serial_device.put_char(c);
+            serial_device.put_char(b']');
+        }
     }
 }
 
diff --git a/hacking/nix/scope/world/instances/default.nix b/hacking/nix/scope/world/instances/default.nix
index 0e5674cf5..5c81a68d5 100644
--- a/hacking/nix/scope/world/instances/default.nix
+++ b/hacking/nix/scope/world/instances/default.nix
@@ -346,7 +346,7 @@ in rec {
         };
       });
 
-      serial-device = maybe (haveFullRuntime && hostPlatform.isAarch) (mkInstance {
+      serial-device = maybe (haveFullRuntime && hostPlatform.isAarch) (lib.fix (self: mkInstance {
         rootTask = mkTask {
           rootCrate = crates.serial-device;
           release = false;
@@ -354,7 +354,19 @@ in rec {
         extraPlatformArgs = lib.optionalAttrs canSimulate {
           canAutomateSimply = true;
         };
-      });
+      } // lib.optionalAttrs canSimulate rec {
+        automate =
+          let
+            py = buildPackages.python3.withPackages (pkgs: [
+              pkgs.pexpect
+            ]);
+          in
+            writeScript "automate" ''
+              #!${buildPackages.runtimeShell}
+              set -eu
+              ${py}/bin/python3 ${./test-automation-scripts/serial-device.py} ${self.simulate}
+            '';
+      }));
 
       spawn-thread = maybe haveFullRuntime (mkInstance {
         rootTask = mkTask {
diff --git a/hacking/nix/scope/world/instances/test-automation-scripts/serial-device.py b/hacking/nix/scope/world/instances/test-automation-scripts/serial-device.py
new file mode 100644
index 000000000..f27a7ee9a
--- /dev/null
+++ b/hacking/nix/scope/world/instances/test-automation-scripts/serial-device.py
@@ -0,0 +1,28 @@
+#
+# Copyright 2023, Colias Group, LLC
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+
+import sys
+import time
+import argparse
+import pexpect
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('simulate')
+    args = parser.parse_args()
+    run(args)
+
+def run(args):
+    child = pexpect.spawn(args.simulate, encoding='utf-8')
+    child.logfile = sys.stdout
+    child.expect('echo> ', timeout=10)
+    time.sleep(5)
+    child.sendline('xxx')
+    child.expect('[x][x][x]', timeout=10)
+    print()
+
+if __name__ == '__main__':
+    main()