diff --git a/CMakeLists.txt b/CMakeLists.txt
index e1b3cbe..5e0b1d4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -8,9 +8,14 @@ project(
 set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_CXX_STANDARD_REQUIRED TRUE)
 
+IF (NOT CMAKE_BUILD_TYPE)
+    MESSAGE(STATUS "CMAKE_BUILD_TYPE IS EMPTY. ASSIGN: RELEASE")
+    SET(CMAKE_BUILD_TYPE RELEASE)
+ENDIF ()
+
 add_subdirectory(3rd)
 add_subdirectory(csrc)
 
 if(EXISTS ${CMAKE_SOURCE_DIR}/tests)
         add_subdirectory(tests)
-endif()
\ No newline at end of file
+endif()
diff --git a/include/pthread_backend.h b/include/pthread_backend.h
index 27a5daa..e27f37f 100644
--- a/include/pthread_backend.h
+++ b/include/pthread_backend.h
@@ -1,7 +1,6 @@
 #pragma once
 
 #include <stdexcept>
-#include <sys/io.h>
 #include <sys/uio.h>
 #include <unistd.h>
 #include <cstdlib>
@@ -59,4 +58,4 @@ class PthreadAsyncIO : public AsyncIO
 
     void write_tensor(int fd, torch::Tensor t, unsigned long long offset, callback_t callback, std::optional<torch::Tensor> pinned);
     void register_tasks(unsigned int num_tasks);
-};
\ No newline at end of file
+};