diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8763546..2f5760d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,10 +16,7 @@
 # limitations under the License.
 #
 
-cmake_minimum_required(VERSION 2.6)
-if(COMMAND cmake_policy)
-  cmake_policy(VERSION 2.6)
-endif(COMMAND cmake_policy)
+cmake_minimum_required(VERSION 3.5)
 
 ### General Package stuff
 project(tmux-mem-cpu-load)
@@ -76,17 +73,17 @@ elseif(CMAKE_SYSTEM_NAME MATCHES "OpenBSD")
 elseif(CMAKE_SYSTEM_NAME MATCHES "NetBSD")
   set(METER_SOURCES "netbsd/memory.cc" "netbsd/cpu.cc" "common/load.cc")
 else()
+  message(FATAL_ERROR "${CMAKE_SYSTEM_NAME} Cannot be compiled on this system")
   message(FATAL_ERROR "Cannot be compiled on this system")
 endif()
 
 # set common source files
 set(COMMON_SOURCES "common/main.cc" "common/memory.cc" "common/graph.cc" "common/powerline.cc")
 
-# add binary tree so we find version.h
-include_directories("${PROJECT_BINARY_DIR}")
-include_directories("${PROJECT_SOURCE_DIR}" "${PROJECT_SOURCE_DIR}/common")
-
 add_executable(tmux-mem-cpu-load ${COMMON_SOURCES} ${METER_SOURCES})
+# add binary tree so we find version.h
+target_include_directories(tmux-mem-cpu-load "${PROJECT_BINARY_DIR}")
+target_include_directories(tmux-mem-cpu-load "${PROJECT_SOURCE_DIR}" "${PROJECT_SOURCE_DIR}/common")
 install(TARGETS tmux-mem-cpu-load RUNTIME DESTINATION bin)
 
 include(CTest)