diff --git a/plugins/synaptics-prometheus/fu-dump.c b/plugins/synaptics-prometheus/fu-dump.c
deleted file mode 100644
index acc2893aa..000000000
--- a/plugins/synaptics-prometheus/fu-dump.c
+++ /dev/null
@@ -1,58 +0,0 @@
-/*
- * Copyright (C) 2019 Richard Hughes <richard@hughsie.com>
- *
- * SPDX-License-Identifier: LGPL-2.1+
- */
-
-#include "config.h"
-
-#include "fu-synaprom-firmware.h"
-
-static gboolean
-fu_dump_parse (const gchar *filename, GError **error)
-{
-	gchar *data = NULL;
-	gsize len = 0;
-	g_autoptr(GBytes) blob = NULL;
-	g_autoptr(FuFirmware) firmware = fu_synaprom_firmware_new ();
-	if (!g_file_get_contents (filename, &data, &len, error))
-		return FALSE;
-	blob = g_bytes_new_take (data, len);
-	return fu_firmware_parse (firmware, blob, 0, error);
-}
-
-static gboolean
-fu_dump_generate (const gchar *filename, GError **error)
-{
-	const gchar *data;
-	gsize len = 0;
-	g_autoptr(GBytes) blob = NULL;
-	g_autoptr(FuFirmware) firmware = fu_synaprom_firmware_new ();
-	blob = fu_firmware_write (firmware, error);
-	if (blob == NULL)
-		return FALSE;
-	data = g_bytes_get_data (blob, &len);
-	return g_file_set_contents (filename, data, len, error);
-}
-
-int
-main (int argc, char **argv)
-{
-	g_autoptr(GError) error = NULL;
-	if (argc == 2) {
-		if (!fu_dump_parse (argv[1], &error)) {
-			g_printerr ("parse failed: %s\n", error->message);
-			return 1;
-		}
-	} else if (argc == 3 && g_strcmp0 (argv[2], "gen") == 0) {
-		if (!fu_dump_generate (argv[1], &error)) {
-			g_printerr ("generate failed: %s\n", error->message);
-			return 1;
-		}
-	} else {
-		g_printerr ("firmware filename required\n");
-		return 2;
-	}
-	g_print ("OK!\n");
-	return 0;
-}
diff --git a/plugins/synaptics-prometheus/fu-synaprom-config.c b/plugins/synaptics-prometheus/fu-synaprom-config.c
index 74f9a5fca..660e7cb24 100644
--- a/plugins/synaptics-prometheus/fu-synaprom-config.c
+++ b/plugins/synaptics-prometheus/fu-synaprom-config.c
@@ -48,6 +48,15 @@ typedef struct __attribute__((packed)) {
 	guint16		 unused[3];
 } FuSynapromIotaConfigVersion;
 
+/* le */
+typedef struct __attribute__((packed)) {
+	guint32			 product;
+	guint32			 id1;			/* verification ID */
+	guint32			 id2;			/* verification ID */
+	guint16			 version;		/* config version */
+	guint8			 unused[2];
+} FuSynapromFirmwareCfgHeader;
+
 #define FU_SYNAPROM_CMD_IOTA_FIND_FLAGS_ALLIOTAS	0x0001	/* itype ignored*/
 #define FU_SYNAPROM_CMD_IOTA_FIND_FLAGS_READMAX		0x0002	/* nbytes ignored */
 #define FU_SYNAPROM_MAX_IOTA_READ_SIZE			(64 * 1024) /* max size of iota data returned */
diff --git a/plugins/synaptics-prometheus/fu-synaprom-firmware.c b/plugins/synaptics-prometheus/fu-synaprom-firmware.c
index efebc584d..c24864439 100644
--- a/plugins/synaptics-prometheus/fu-synaprom-firmware.c
+++ b/plugins/synaptics-prometheus/fu-synaprom-firmware.c
@@ -14,10 +14,16 @@
 
 struct _FuSynapromFirmware {
 	FuFirmware		 parent_instance;
+	guint32			 product_id;
 };
 
 G_DEFINE_TYPE (FuSynapromFirmware, fu_synaprom_firmware, FU_TYPE_FIRMWARE)
 
+#define FU_SYNAPROM_FIRMWARE_TAG_MFW_HEADER		0x0001
+#define FU_SYNAPROM_FIRMWARE_TAG_MFW_PAYLOAD		0x0002
+#define FU_SYNAPROM_FIRMWARE_TAG_CFG_HEADER		0x0003
+#define FU_SYNAPROM_FIRMWARE_TAG_CFG_PAYLOAD		0x0004
+
 typedef struct __attribute__((packed)) {
 	guint16			 tag;
 	guint32			 bufsz;
@@ -41,6 +47,13 @@ fu_synaprom_firmware_tag_to_string (guint16 tag)
 	return NULL;
 }
 
+static void
+fu_synaprom_firmware_to_string (FuFirmware *firmware, guint idt, GString *str)
+{
+	FuSynapromFirmware *self = FU_SYNAPROM_FIRMWARE (firmware);
+	fu_common_string_append_kx (str, idt, "ProductId", self->product_id);
+}
+
 static gboolean
 fu_synaprom_firmware_parse (FuFirmware *firmware,
 			    GBytes *fw,
@@ -116,12 +129,13 @@ fu_synaprom_firmware_parse (FuFirmware *firmware,
 }
 
 static GBytes *
-fu_synaprom_firmware_write (FuFirmware *self, GError **error)
+fu_synaprom_firmware_write (FuFirmware *firmware, GError **error)
 {
+	FuSynapromFirmware *self = FU_SYNAPROM_FIRMWARE (firmware);
 	GByteArray *blob = g_byte_array_new ();
-	const guint8 data[] = { 'R', 'H' };
+	g_autoptr(GBytes) payload = NULL;
 	FuSynapromFirmwareMfwHeader hdr = {
-		.product	= GUINT32_TO_LE(0x41),
+		.product	= GUINT32_TO_LE(self->product_id),
 		.id 		= GUINT32_TO_LE(0xff),
 		.buildtime	= GUINT32_TO_LE(0xff),
 		.buildnum	= GUINT32_TO_LE(0xff),
@@ -130,14 +144,27 @@ fu_synaprom_firmware_write (FuFirmware *self, GError **error)
 	};
 
 	/* add header */
-	fu_byte_array_append_uint16 (blob, FU_SYNAPROM_FIRMWARE_TAG_MFW_HEADER, G_LITTLE_ENDIAN);
-	fu_byte_array_append_uint32 (blob, sizeof(hdr), G_LITTLE_ENDIAN);
+	fu_byte_array_append_uint16 (blob,
+				     FU_SYNAPROM_FIRMWARE_TAG_MFW_HEADER,
+				     G_LITTLE_ENDIAN);
+	fu_byte_array_append_uint32 (blob,
+				     sizeof(hdr),
+				     G_LITTLE_ENDIAN);
 	g_byte_array_append (blob, (const guint8 *) &hdr, sizeof(hdr));
 
 	/* add payload */
-	fu_byte_array_append_uint16 (blob, FU_SYNAPROM_FIRMWARE_TAG_MFW_PAYLOAD, G_LITTLE_ENDIAN);
-	fu_byte_array_append_uint32 (blob, sizeof(data), G_LITTLE_ENDIAN);
-	g_byte_array_append (blob, data, sizeof(data));
+	payload = fu_firmware_get_image_default_bytes (firmware, error);
+	if (payload == NULL)
+		return FALSE;
+	fu_byte_array_append_uint16 (blob,
+				     FU_SYNAPROM_FIRMWARE_TAG_MFW_PAYLOAD,
+				     G_LITTLE_ENDIAN);
+	fu_byte_array_append_uint32 (blob,
+				     g_bytes_get_size (payload),
+				     G_LITTLE_ENDIAN);
+	g_byte_array_append (blob,
+			     g_bytes_get_data (payload, NULL),
+			     g_bytes_get_size (payload));
 
 	/* add signature */
 	for (guint i = 0; i < FU_SYNAPROM_FIRMWARE_SIGSIZE; i++)
@@ -145,6 +172,21 @@ fu_synaprom_firmware_write (FuFirmware *self, GError **error)
 	return g_byte_array_free_to_bytes (blob);
 }
 
+static gboolean
+fu_synaprom_firmware_build (FuFirmware *firmware, XbNode *n, GError **error)
+{
+	FuSynapromFirmware *self = FU_SYNAPROM_FIRMWARE (firmware);
+	guint64 tmp;
+
+	/* simple properties */
+	tmp = xb_node_query_text_as_uint (n, "product_id", NULL);
+	if (tmp != G_MAXUINT64 && tmp <= G_MAXUINT32)
+		self->product_id = tmp;
+
+	/* success */
+	return TRUE;
+}
+
 static void
 fu_synaprom_firmware_init (FuSynapromFirmware *self)
 {
@@ -156,6 +198,8 @@ fu_synaprom_firmware_class_init (FuSynapromFirmwareClass *klass)
 	FuFirmwareClass *klass_firmware = FU_FIRMWARE_CLASS (klass);
 	klass_firmware->parse = fu_synaprom_firmware_parse;
 	klass_firmware->write = fu_synaprom_firmware_write;
+	klass_firmware->to_string = fu_synaprom_firmware_to_string;
+	klass_firmware->build = fu_synaprom_firmware_build;
 }
 
 FuFirmware *
diff --git a/plugins/synaptics-prometheus/fu-synaprom-firmware.h b/plugins/synaptics-prometheus/fu-synaprom-firmware.h
index 6e7733ff2..fb983f494 100644
--- a/plugins/synaptics-prometheus/fu-synaprom-firmware.h
+++ b/plugins/synaptics-prometheus/fu-synaprom-firmware.h
@@ -8,16 +8,10 @@
 #pragma once
 
 #include "fu-firmware.h"
-#include "fu-synaprom-firmware.h"
 
 #define FU_TYPE_SYNAPROM_FIRMWARE (fu_synaprom_firmware_get_type ())
 G_DECLARE_FINAL_TYPE (FuSynapromFirmware, fu_synaprom_firmware, FU, SYNAPROM_FIRMWARE, FuFirmware)
 
-#define FU_SYNAPROM_FIRMWARE_TAG_MFW_HEADER		0x0001
-#define FU_SYNAPROM_FIRMWARE_TAG_MFW_PAYLOAD		0x0002
-#define FU_SYNAPROM_FIRMWARE_TAG_CFG_HEADER		0x0003
-#define FU_SYNAPROM_FIRMWARE_TAG_CFG_PAYLOAD		0x0004
-
 /* le */
 typedef struct __attribute__((packed)) {
 	guint32			 product;
@@ -29,13 +23,4 @@ typedef struct __attribute__((packed)) {
 	guint8			 unused[6];
 } FuSynapromFirmwareMfwHeader;
 
-/* le */
-typedef struct __attribute__((packed)) {
-	guint32			 product;
-	guint32			 id1;			/* verification ID */
-	guint32			 id2;			/* verification ID */
-	guint16			 version;		/* config version */
-	guint8			 unused[2];
-} FuSynapromFirmwareCfgHeader;
-
 FuFirmware		*fu_synaprom_firmware_new	(void);
diff --git a/plugins/synaptics-prometheus/meson.build b/plugins/synaptics-prometheus/meson.build
index fed45214c..b29cc931e 100644
--- a/plugins/synaptics-prometheus/meson.build
+++ b/plugins/synaptics-prometheus/meson.build
@@ -61,27 +61,4 @@ if get_option('tests')
     install_dir : installed_test_bindir,
   )
   test('synaptics-prometheus-self-test', e, env : testdatadirs)  # added to installed-tests
-
-  # for fuzzing
-  executable(
-    'synaptics-prometheus-dump',
-    sources : [
-      'fu-dump.c',
-      'fu-synaprom-firmware.c',
-    ],
-    include_directories : [
-      root_incdir,
-      fwupd_incdir,
-      fwupdplugin_incdir,
-    ],
-    dependencies : [
-      gio,
-      libxmlb,
-    ],
-    link_with : [
-      fwupd,
-      fwupdplugin,
-    ],
-    c_args : cargs
-  )
 endif