diff --git a/Makefile b/Makefile
index 4810c34..9c0a336 100644
--- a/Makefile
+++ b/Makefile
@@ -1026,6 +1026,11 @@
 strip: $(PROGRAM)$(EXEC_SUFFIX)
 	$(STRIP) $(STRIP_ARGS) $(PROGRAM)$(EXEC_SUFFIX)
 
+additional_tests: CPPFLAGS += -Iinclude/test
+ifeq ($(CONFIG_NI845X_SPI), no)
+additional_tests: ni845x_spi.o
+endif
+
 # Make sure to add all names of generated binaries here.
 # This includes all frontends and libflashprog.
 # We don't use EXEC_SUFFIX here because we want to clean everything.
@@ -1116,7 +1121,8 @@
 gitconfig:
 	./util/getrevision.sh -c 2>/dev/null && ./util/git-hooks/install.sh
 
-.PHONY: all install clean distclean config branch tag versioninfo _export export tarball libpayload gitconfig
+.PHONY: all install clean distclean config additional_tests branch tag
+.PHONY: versioninfo _export export tarball libpayload gitconfig
 
 # Disable implicit suffixes and built-in rules (for performance and profit)
 .SUFFIXES:
diff --git a/include/test/ni845x.h b/include/test/ni845x.h
new file mode 100644
index 0000000..cd6a56b
--- /dev/null
+++ b/include/test/ni845x.h
@@ -0,0 +1,58 @@
+/*
+ * This file is part of the flashrom project.
+ *
+ * Copyright (C) 2026 Nico Huber <nico.h@gmx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+/*
+ * This file is merely mimicking the expected API, so we
+ * can build test the ni845x_spi driver. Everything in
+ * here is derived from the usage in `ni845x_spi.c`.
+ */
+
+#ifndef __NI845X_H__
+#define __NI845X_H__ 1
+
+#include <stdint.h>
+
+typedef uint8_t		uInt8;
+typedef uint16_t	uInt16;
+typedef uint32_t	uInt32;
+typedef int32_t		int32;
+typedef uInt32		NiHandle;
+
+enum {
+	kNi845x12Volts,
+	kNi845x15Volts,
+	kNi845x18Volts,
+	kNi845x25Volts,
+	kNi845x33Volts,
+};
+
+void ni845xStatusToString(int32 err, uInt32 buf_size, char *buf);
+
+int32 ni845xFindDevice(char *resource_name, NiHandle *, uInt32 *found_devices_count);
+int32 ni845xFindDeviceNext(NiHandle, char *resource_name);
+int32 ni845xCloseFindDeviceHandle(NiHandle);
+
+int32 ni845xOpen(char *resource_name, uInt32 *opened_handle);
+int32 ni845xSetIoVoltageLevel(uInt32 device_handle, uInt8 selected_voltage_100mV);
+int32 ni845xClose(uInt32 device_handle);
+
+int32 ni845xSpiConfigurationOpen(NiHandle *);
+int32 ni845xSpiConfigurationSetClockRate(NiHandle, uInt16 SCK_freq_in_KHz);
+int32 ni845xSpiConfigurationGetClockRate(NiHandle, uInt16 *clock_freq_read_KHz);
+int32 ni845xSpiWriteRead(uInt32 device_handle, NiHandle, uInt32 write_size, const uInt8 *write_buf, uInt32 *read_size, uInt8 *read_buf);
+int32 ni845xSpiConfigurationClose(NiHandle);
+
+#endif				/* !__NI845X_H__ */
diff --git a/test_build.sh b/test_build.sh
index 17d1caa..7fb3239 100755
--- a/test_build.sh
+++ b/test_build.sh
@@ -29,7 +29,7 @@
 build_and_test() {
 	if [ "${MAKECMD=make}" ]; then
 		${MAKECMD} clean
-		eval ${MAKECMD} -j${CPUS:-$(nproc)} CC="\"${CC}\"" ${MAKEARGS-CONFIG_EVERYTHING=yes}
+		eval ${MAKECMD} -j${CPUS:-$(nproc)} CC="\"${CC}\"" ${MAKEARGS-CONFIG_EVERYTHING=yes all additional_tests}
 		test_prog ./flashprog
 	fi
 
diff --git a/util/manibuilder/Makefile b/util/manibuilder/Makefile
index 7109ce2..a9be1fe 100644
--- a/util/manibuilder/Makefile
+++ b/util/manibuilder/Makefile
@@ -4,7 +4,7 @@
 
 CC := ccache cc
 MAKECMD := make
-MAKEARGS := CONFIG_EVERYTHING=yes
+MAKEARGS := CONFIG_EVERYTHING=yes all additional_tests
 MESONCMD := meson
 MESONARGS := -D programmer=all -D classic_cli_print_wiki=enabled --auto-features enabled