diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2cadabae..b09d1af7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -129,7 +129,7 @@ include (${CMAKE_MODULE_PATH}/platform.cmake)
 # Detect OS and if Fat Runtime is available
 include (${CMAKE_MODULE_PATH}/osdetection.cmake)
 
-if(ARCH_X86_86 AND BUILD_SSE2_SIMDE AND NOT FAT_RUNTIME)
+if(ARCH_X86_64 AND BUILD_SSE2_SIMDE AND NOT FAT_RUNTIME)
     set(SIMDE_BACKEND True)
 endif()
 
diff --git a/cmake/simde.cmake b/cmake/simde.cmake
index 9cfaaf4b..9b15e177 100644
--- a/cmake/simde.cmake
+++ b/cmake/simde.cmake
@@ -20,15 +20,19 @@ if (SIMDE_SSE42_H_FOUND)
     endif()
   endif()
 
-  if (SIMDE_NATIVE)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DVS_SIMDE_NATIVE -DSIMDE_ENABLE_OPENMP -fopenmp-simd")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DVS_SIMDE_NATIVE -DSIMDE_ENABLE_OPENMP -fopenmp-simd")
+  if (BUILD_SSE2_SIMDE)
+    message("using BUILD_SSE2_SIMDE..")
+    set(SIMDE_NATIVE true)
+    set(ARCH_C_FLAGS "-msse2")
+    set(ARCH_CXX_FLAGS "-msse2")
+    set(X86_ARCH "x86-64")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DVS_SIMDE_NATIVE -DVS_SIMDE_BACKEND")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DVS_SIMDE_NATIVE -DVS_SIMDE_BACKEND")
   endif()
 
-  if (BUILD_SSE2_SIMDE)
-      set(ARCH_C_FLAGS "-msse2")
-      set(ARCH_CXX_FLAGS "-msse2")
-      set(X86_ARCH "x86-64")
+  if (SIMDE_NATIVE AND NOT BUILD_SSE2_SIMDE)
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DVS_SIMDE_NATIVE -DSIMDE_ENABLE_OPENMP -fopenmp-simd")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DVS_SIMDE_NATIVE -DSIMDE_ENABLE_OPENMP -fopenmp-simd")
   endif()
 
 else()