diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 1560c0a..61ad45f 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -14,6 +14,12 @@ add_library(md5 STATIC ../third_party/md5/md5.cpp)
 
 ################################################################################
 
+unset(CMAKE_ARCHIVE_OUTPUT_DIRECTORY)
+include_directories(../third_party/tiny_thread_pool/src)
+add_library(tiny_pool STATIC ../third_party/tiny_thread_pool/src/tiny_pool.c)
+
+################################################################################
+
 include_directories(../src/klotski_core/utils)
 include_directories(../src/klotski_core/all_cases)
 
@@ -47,3 +53,17 @@ target_link_libraries(test_ffi ${TEST_DEPS})
 add_test(NAME ffi COMMAND test_ffi)
 
 ################################################################################
+
+include_directories(../src/klotski_core)
+
+add_library(test_global_utils STATIC global/utils.cc)
+
+add_executable(test_global_common_code global/common_code.cc)
+
+target_link_libraries(test_global_common_code test_global_utils tiny_pool)
+
+target_link_libraries(test_global_common_code ${TEST_DEPS})
+
+add_test(NAME global_common_code COMMAND test_global_common_code)
+
+################################################################################
diff --git a/test/global/common_code.cc b/test/global/common_code.cc
new file mode 100644
index 0000000..d4d168d
--- /dev/null
+++ b/test/global/common_code.cc
@@ -0,0 +1,8 @@
+#include "klotski.h"
+#include "gtest/gtest.h"
+
+TEST(GLOBAL, common_code) {
+
+//    std::cout << "demo ok" << std::endl;
+
+}
diff --git a/test/global/utils.cc b/test/global/utils.cc
new file mode 100644
index 0000000..d3a9edd
--- /dev/null
+++ b/test/global/utils.cc
@@ -0,0 +1,37 @@
+#include <future>
+#include <functional>
+#include "tiny_pool.h"
+
+class TinyPool { // OOP for tiny_thread_pool
+    pool_t *pool;
+    static void wrap_c_func(void *func) { // wrap std::function as c-style function ptr
+        (*static_cast<std::function<void()>*>(func))();
+        free(func);
+    }
+
+public:
+    void boot() { tiny_pool_boot(pool); }
+    void join() { tiny_pool_join(pool); }
+    void kill() { tiny_pool_kill(pool); }
+    void detach() { tiny_pool_detach(pool); }
+    explicit TinyPool(uint32_t size) { pool = tiny_pool_create(size); }
+
+    template <typename Func, typename ...Args>
+    auto submit(Func &&func, Args &&...args) -> std::future<decltype(func(args...))>;
+};
+
+template <typename Func, typename ...Args>
+auto TinyPool::submit(Func &&func, Args &&...args) -> std::future<decltype(func(args...))> {
+    std::function<decltype(func(args...))()> wrap_func = std::bind(
+        std::forward<Func>(func), std::forward<Args>(args)...
+    );
+    auto func_ptr = std::make_shared<
+        std::packaged_task<decltype(func(args...))()>
+    >(wrap_func);
+    tiny_pool_submit(pool, TinyPool::wrap_c_func, (void*)(
+        new std::function<void()> (
+            [func_ptr]() { (*func_ptr)(); }
+        )
+    ));
+    return func_ptr->get_future();
+}