diff --git a/src/test/modules/foo/Makefile b/src/test/modules/foo/Makefile
new file mode 100644
index 0000000..da13e65
--- /dev/null
+++ b/src/test/modules/foo/Makefile
@@ -0,0 +1,18 @@
+# src/test/modules/foo/Makefile
+
+MODULES = foo
+
+EXTENSION = foo
+DATA = foo--1.0.sql
+PGFILEDESC = "foo -- a random testing/hacking extension"
+
+ifdef USE_PGXS
+PG_CONFIG = pg_config
+PGXS := $(shell $(PG_CONFIG) --pgxs)
+include $(PGXS)
+else
+subdir = src/test/modules/foo
+top_builddir = ../../../..
+include $(top_builddir)/src/Makefile.global
+include $(top_srcdir)/contrib/contrib-global.mk
+endif
diff --git a/src/test/modules/foo/foo--1.0.sql b/src/test/modules/foo/foo--1.0.sql
new file mode 100644
index 0000000..bc12ebd
--- /dev/null
+++ b/src/test/modules/foo/foo--1.0.sql
@@ -0,0 +1,8 @@
+\echo Use "CREATE EXTENSION foo" to load this file. \quit
+
+CREATE FUNCTION test_dsm(size bigint)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C;
+
+
diff --git a/src/test/modules/foo/foo.c b/src/test/modules/foo/foo.c
new file mode 100644
index 0000000..6c3ebad
--- /dev/null
+++ b/src/test/modules/foo/foo.c
@@ -0,0 +1,25 @@
+#include "postgres.h"
+
+#include "fmgr.h"
+#include "funcapi.h"
+#include "miscadmin.h"
+#include "storage/dsm.h"
+#include "utils/builtins.h"
+
+PG_MODULE_MAGIC;
+
+PG_FUNCTION_INFO_V1(test_dsm);
+
+Datum
+test_dsm(PG_FUNCTION_ARGS)
+{
+	size_t size = PG_GETARG_INT64(0);
+	void *data;
+
+	dsm_segment *segment = dsm_create(size, 0);
+	data = dsm_segment_address(segment);
+	memset(data, 0, size);
+	dsm_detach(segment);
+
+	PG_RETURN_VOID();
+}
diff --git a/src/test/modules/foo/foo.control b/src/test/modules/foo/foo.control
new file mode 100644
index 0000000..af1b50a
--- /dev/null
+++ b/src/test/modules/foo/foo.control
@@ -0,0 +1,4 @@
+comment = 'foo'
+default_version = '1.0'
+module_pathname = '$libdir/foo'
+relocatable = true