diff --git a/fw/cmake/gcc-arm-none-eabi.cmake b/fw/cmake/gcc-arm-none-eabi.cmake
index 97decf7..dc3446a 100644
--- a/fw/cmake/gcc-arm-none-eabi.cmake
+++ b/fw/cmake/gcc-arm-none-eabi.cmake
@@ -29,9 +29,9 @@ set(CMAKE_ASM_FLAGS "${CMAKE_C_FLAGS} -x assembler-with-cpp -MMD -MP")
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -fdata-sections -ffunction-sections")
 
 set(CMAKE_C_FLAGS_DEBUG "-O0 -g3")
-set(CMAKE_C_FLAGS_RELEASE "-Os -g0")
+set(CMAKE_C_FLAGS_RELEASE "-O3 -g0")
 set(CMAKE_CXX_FLAGS_DEBUG "-O0 -g3")
-set(CMAKE_CXX_FLAGS_RELEASE "-Os -g0")
+set(CMAKE_CXX_FLAGS_RELEASE "-O3 -g0")
 
 set(CMAKE_CXX_FLAGS "${CMAKE_C_FLAGS} -fno-rtti -fno-exceptions -fno-threadsafe-statics")