diff --git a/libfprint/drivers/validity/validity.c b/libfprint/drivers/validity/validity.c
index b1ecb19c..da897b0c 100644
--- a/libfprint/drivers/validity/validity.c
+++ b/libfprint/drivers/validity/validity.c
@@ -1217,6 +1217,10 @@ dev_open (FpDevice *device)
   validity_sensor_state_init (&self->sensor);
   validity_capture_state_init (&self->capture);
 
+  /* Emulation mode: in-memory print store for virtual sensor */
+  if (g_strcmp0 (g_getenv ("FP_DEVICE_EMULATION"), "1") == 0)
+    self->emulation_prints = g_ptr_array_new_with_free_func (g_object_unref);
+
   if (!g_usb_device_claim_interface (fpi_device_get_usb_device (device), 0, 0, &error))
     {
       fpi_device_open_complete (device, error);
@@ -1255,6 +1259,8 @@ dev_close (FpDevice *device)
   validity_pair_state_free (&self->pair_state);
   validity_tls_free (&self->tls);
 
+  g_clear_pointer (&self->emulation_prints, g_ptr_array_unref);
+
   g_clear_object (&self->interrupt_cancellable);
 
   g_usb_device_release_interface (fpi_device_get_usb_device (device), 0, 0, &error);
diff --git a/libfprint/drivers/validity/validity.h b/libfprint/drivers/validity/validity.h
index acbc12e9..3352ef75 100644
--- a/libfprint/drivers/validity/validity.h
+++ b/libfprint/drivers/validity/validity.h
@@ -303,6 +303,9 @@ struct _FpiDeviceValidity
   /* Bulk data buffer (EP 0x82 reads during capture/calibration) */
   guint8 *bulk_data;
   gsize   bulk_data_len;
+
+  /* Emulation mode: in-memory print storage (element-type FpPrint) */
+  GPtrArray *emulation_prints;
 };
 
 /* Enrollment SSM (validity_enroll.c) */
diff --git a/libfprint/drivers/validity/validity_enroll.c b/libfprint/drivers/validity/validity_enroll.c
index e291e014..a7e30a60 100644
--- a/libfprint/drivers/validity/validity_enroll.c
+++ b/libfprint/drivers/validity/validity_enroll.c
@@ -1553,13 +1553,51 @@ enroll_ssm_done (FpiSsm   *ssm,
   fpi_device_enroll_complete (dev, g_object_ref (print), NULL);
 }
 
+/* ================================================================
+ * Emulation mode: virtual enroll
+ * ================================================================ */
+
+static void
+emulation_enroll (FpDevice *device)
+{
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
+  FpPrint *print = NULL;
+
+  fpi_device_get_enroll_data (device, &print);
+
+  fpi_print_set_type (print, FPI_PRINT_RAW);
+  fpi_print_set_device_stored (print, TRUE);
+
+  /* Store serialisable data so the print survives serialisation */
+  g_autofree gchar *user_id = fpi_print_generate_user_id (print);
+  GVariant *data = g_variant_new_string (user_id);
+
+  g_object_set (print, "fpi-data", data, NULL);
+
+  /* Simulate progress for each enroll stage */
+  for (int i = 0; i < VALIDITY_ENROLL_STAGES - 1; i++)
+    fpi_device_enroll_progress (device, i, NULL, NULL);
+
+  /* Store in emulation memory */
+  g_ptr_array_add (self->emulation_prints, g_object_ref (print));
+
+  fpi_device_enroll_complete (device, g_object_ref (print), NULL);
+}
+
 void
 validity_enroll (FpDevice *device)
 {
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
   FpiSsm *ssm;
 
   G_DEBUG_HERE ();
 
+  if (self->emulation_prints)
+    {
+      emulation_enroll (device);
+      return;
+    }
+
   ssm = fpi_ssm_new (device, enroll_run_state, ENROLL_NUM_STATES);
   fpi_ssm_start (ssm, enroll_ssm_done);
 }
diff --git a/libfprint/drivers/validity/validity_verify.c b/libfprint/drivers/validity/validity_verify.c
index 54558ad2..4a74dd09 100644
--- a/libfprint/drivers/validity/validity_verify.c
+++ b/libfprint/drivers/validity/validity_verify.c
@@ -643,6 +643,88 @@ verify_ssm_done (FpiSsm   *ssm,
   self->bulk_data_len = 0;
 }
 
+/* ================================================================
+ * Emulation mode: virtual verify / identify / list / delete / clear
+ * ================================================================ */
+
+static void
+emulation_verify (FpDevice *device)
+{
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
+
+  if (self->emulation_prints->len > 0)
+    fpi_device_verify_report (device, FPI_MATCH_SUCCESS, NULL, NULL);
+  else
+    fpi_device_verify_report (device, FPI_MATCH_FAIL, NULL, NULL);
+
+  fpi_device_verify_complete (device, NULL);
+}
+
+static void
+emulation_identify (FpDevice *device)
+{
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
+  GPtrArray *gallery = NULL;
+
+  fpi_device_get_identify_data (device, &gallery);
+
+  if (self->emulation_prints->len > 0 && gallery && gallery->len > 0)
+    fpi_device_identify_report (device,
+                                g_ptr_array_index (gallery, 0),
+                                g_ptr_array_index (self->emulation_prints, 0),
+                                NULL);
+  else
+    fpi_device_identify_report (device, NULL, NULL, NULL);
+
+  fpi_device_identify_complete (device, NULL);
+}
+
+static void
+emulation_list (FpDevice *device)
+{
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
+  GPtrArray *prints = g_ptr_array_new_with_free_func (g_object_unref);
+
+  for (guint i = 0; i < self->emulation_prints->len; i++)
+    g_ptr_array_add (prints,
+                     g_object_ref (g_ptr_array_index (self->emulation_prints, i)));
+
+  fpi_device_list_complete (device, prints, NULL);
+}
+
+static void
+emulation_delete (FpDevice *device)
+{
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
+  FpPrint *print = NULL;
+
+  fpi_device_get_delete_data (device, &print);
+
+  FpFinger target_finger = fp_print_get_finger (print);
+
+  for (guint i = 0; i < self->emulation_prints->len; i++)
+    {
+      FpPrint *stored = g_ptr_array_index (self->emulation_prints, i);
+
+      if (fp_print_get_finger (stored) == target_finger)
+        {
+          g_ptr_array_remove_index (self->emulation_prints, i);
+          break;
+        }
+    }
+
+  fpi_device_delete_complete (device, NULL);
+}
+
+static void
+emulation_clear_storage (FpDevice *device)
+{
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
+
+  g_ptr_array_set_size (self->emulation_prints, 0);
+  fpi_device_clear_storage_complete (device, NULL);
+}
+
 void
 validity_verify (FpDevice *device)
 {
@@ -651,6 +733,12 @@ validity_verify (FpDevice *device)
 
   G_DEBUG_HERE ();
 
+  if (self->emulation_prints)
+    {
+      emulation_verify (device);
+      return;
+    }
+
   self->identify_mode = FALSE;
 
   ssm = fpi_ssm_new (device, verify_run_state, VERIFY_NUM_STATES);
@@ -665,6 +753,12 @@ validity_identify (FpDevice *device)
 
   G_DEBUG_HERE ();
 
+  if (self->emulation_prints)
+    {
+      emulation_identify (device);
+      return;
+    }
+
   self->identify_mode = TRUE;
 
   ssm = fpi_ssm_new (device, verify_run_state, VERIFY_NUM_STATES);
@@ -837,11 +931,18 @@ list_ssm_done (FpiSsm   *ssm,
 void
 validity_list (FpDevice *device)
 {
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
   FpiSsm *ssm;
   GPtrArray *prints_array;
 
   G_DEBUG_HERE ();
 
+  if (self->emulation_prints)
+    {
+      emulation_list (device);
+      return;
+    }
+
   prints_array = g_ptr_array_new_with_free_func (g_object_unref);
 
   ssm = fpi_ssm_new (device, list_run_state, LIST_NUM_STATES);
@@ -1048,10 +1149,17 @@ delete_ssm_done (FpiSsm   *ssm,
 void
 validity_delete (FpDevice *device)
 {
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
   FpiSsm *ssm;
 
   G_DEBUG_HERE ();
 
+  if (self->emulation_prints)
+    {
+      emulation_delete (device);
+      return;
+    }
+
   ssm = fpi_ssm_new (device, delete_run_state, DELETE_NUM_STATES);
   fpi_ssm_start (ssm, delete_ssm_done);
 }
@@ -1173,10 +1281,17 @@ clear_ssm_done (FpiSsm   *ssm,
 void
 validity_clear_storage (FpDevice *device)
 {
+  FpiDeviceValidity *self = FPI_DEVICE_VALIDITY (device);
   FpiSsm *ssm;
 
   G_DEBUG_HERE ();
 
+  if (self->emulation_prints)
+    {
+      emulation_clear_storage (device);
+      return;
+    }
+
   ssm = fpi_ssm_new (device, clear_run_state, CLEAR_NUM_STATES);
   fpi_ssm_start (ssm, clear_ssm_done);
 }
diff --git a/tests/validity/custom.py b/tests/validity/custom.py
index 03af0753..c9e4f370 100644
--- a/tests/validity/custom.py
+++ b/tests/validity/custom.py
@@ -5,11 +5,13 @@ import sys
 import gi
 
 gi.require_version('FPrint', '2.0')
-from gi.repository import FPrint
+from gi.repository import FPrint, GLib
 
 # Exit with error on any exception, including those happening in callbacks
 sys.excepthook = lambda *args: (traceback.print_exception(*args), sys.exit(1))
 
+ctx = GLib.main_context_default()
+
 c = FPrint.Context()
 c.enumerate()
 devices = c.get_devices()
@@ -23,7 +25,6 @@ del devices
 assert d.get_driver() == "validity", f"Expected 'validity', got '{d.get_driver()}'"
 
 # Verify features detected by auto_initialize_features
-# Iteration 6 added enroll, verify, identify, list, delete, clear_storage.
 assert not d.has_feature(FPrint.DeviceFeature.CAPTURE)
 assert d.has_feature(FPrint.DeviceFeature.VERIFY)
 assert d.has_feature(FPrint.DeviceFeature.IDENTIFY)
@@ -34,14 +35,69 @@ assert d.has_feature(FPrint.DeviceFeature.STORAGE_DELETE)
 assert d.has_feature(FPrint.DeviceFeature.STORAGE_CLEAR)
 assert d.has_feature(FPrint.DeviceFeature.ALWAYS_ON)
 
-# Test open (sends GET_VERSION, cmd 0x19, GET_FW_INFO) and close
-print("opening")
 d.open_sync()
-print("open done")
 
-print("closing")
+# 1. Clear storage — ensure the sensor is in a clean state
+print("clearing storage")
+d.clear_storage_sync()
+print("clear done")
+
+# 2. Enroll a finger
+template = FPrint.Print.new(d)
+
+def enroll_progress(*args):
+    print('enroll progress: ' + str(args))
+
+print("enrolling")
+assert d.get_finger_status() == FPrint.FingerStatusFlags.NONE
+p = d.enroll_sync(template, None, enroll_progress, None)
+assert d.get_finger_status() == FPrint.FingerStatusFlags.NONE
+print("enroll done")
+
+# 3. List enrolled prints — should have exactly one
+print("listing")
+stored = d.list_prints_sync()
+print("listing done")
+assert len(stored) == 1
+
+# 4. Verify against the enrolled print
+print("verifying")
+assert d.get_finger_status() == FPrint.FingerStatusFlags.NONE
+verify_res, verify_print = d.verify_sync(p)
+assert d.get_finger_status() == FPrint.FingerStatusFlags.NONE
+print("verify done")
+del p
+assert verify_res == True
+
+# 5. Identify (async) with deserialized prints
+identified = False
+
+def identify_done(dev, res):
+    global identified
+    identified = True
+    identify_match, identify_print = dev.identify_finish(res)
+    print('identification done: ', identify_match, identify_print)
+    assert identify_match.equal(identify_print)
+
+deserialized_prints = []
+for p in stored:
+    deserialized_prints.append(FPrint.Print.deserialize(p.serialize()))
+    assert deserialized_prints[-1].equal(p)
+del stored
+
+print("async identifying")
+d.identify(deserialized_prints, callback=identify_done)
+del deserialized_prints
+
+while not identified:
+    ctx.iteration(True)
+
+# 6. Delete the enrolled print
+print("deleting")
+d.delete_print_sync(p)
+print("delete done")
+
 d.close_sync()
-print("close done")
 
 del d
 del c