diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5e1abd6..5bb8a4b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,17 +3,29 @@ cmake_minimum_required(VERSION 2.8)
 
 project(gpu-stream)
 
-set(CMAKE_SOURCE_DIR src/)
+set(gpu-stream_VERSION_MAJOR 2)
+set(gpu-stream_VERSION_MINOR 0)
 
 list(APPEND CMAKE_CXX_FLAGS --std=c++11)
 
-find_package(CUDA REQUIRED)
-
+find_package(CUDA QUIET)
+if (${CUDA_FOUND})
+set(IMPLEMENTATION CUDA)
+configure_file(src/common.h.in src/common_cuda.h)
 cuda_add_executable(cuda.exe src/main.cpp src/CUDAStream.cu)
 target_compile_definitions(cuda.exe PUBLIC CUDA)
+else (${CUDA_FOUND})
+message("Skipping CUDA...")
+endif (${CUDA_FOUND})
 
-find_package(OpenCL)
+find_package(OpenCL QUIET)
+if (${OpenCL_FOUND})
+set(gpu-stream_IMPLEMENTATION OpenCL)
+configure_file(src/common.h.in src/common_ocl.h)
 add_executable(ocl.exe src/main.cpp src/OCLStream.cpp)
 target_compile_definitions(ocl.exe PUBLIC OCL)
 target_link_libraries(ocl.exe ${OpenCL_LIBRARY})
+else (${OpenCL_FOUND})
+message("Skipping OpenCL...")
+endif (${OpenCL_FOUND})
 
diff --git a/src/common.h b/src/common.h
deleted file mode 100644
index c4bdadb..0000000
--- a/src/common.h
+++ /dev/null
@@ -1,4 +0,0 @@
-
-#define VERSION_STRING "2.0"
-#define IMPLEMENTATION_STRING "CUDA"
-
diff --git a/src/common.h.in b/src/common.h.in
new file mode 100644
index 0000000..44dc040
--- /dev/null
+++ b/src/common.h.in
@@ -0,0 +1,4 @@
+
+#define VERSION_STRING "@gpu-stream_VERSION_MAJOR@.@gpu-stream_VERSION_MINOR@"
+#define IMPLEMENTATION_STRING "@gpu-stream_IMPLEMENTATION@"
+