diff --git a/CMakeLists.txt b/CMakeLists.txt
index ccfd8cd..c7d190a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -46,6 +46,7 @@ target_compile_options(${EXECUTABLE} PRIVATE
 	-Wall
 	-Wpedantic
 	-Wno-unused-parameter
+	-Os								# Optimize for size (that uses O2)
 )
 
 # Linker options
diff --git a/cmake/gcc-arm-none-eabi.cmake b/cmake/gcc-arm-none-eabi.cmake
index a110017..bb598df 100644
--- a/cmake/gcc-arm-none-eabi.cmake
+++ b/cmake/gcc-arm-none-eabi.cmake
@@ -1,21 +1,21 @@
-set(CMAKE_SYSTEM_NAME               Generic)
-set(CMAKE_SYSTEM_PROCESSOR          arm)
-
-# Some default GCC settings
-# arm-none-eabi- must be part of path environment
-set(TOOLCHAIN_PREFIX                arm-none-eabi-)
-set(FLAGS                           "-fdata-sections -ffunction-sections --specs=nano.specs -Wl,--gc-sections")
-set(CPP_FLAGS                       "-fno-rtti -fno-exceptions -fno-threadsafe-statics")
-
-# Define compiler settings
-set(CMAKE_C_COMPILER                ${TOOLCHAIN_PREFIX}gcc ${FLAGS})
-set(CMAKE_ASM_COMPILER              ${CMAKE_C_COMPILER})
-set(CMAKE_CXX_COMPILER              ${TOOLCHAIN_PREFIX}g++ ${FLAGS} ${CPP_FLAGS})
-set(CMAKE_OBJCOPY                   ${TOOLCHAIN_PREFIX}objcopy)
-set(CMAKE_SIZE                      ${TOOLCHAIN_PREFIX}size)
-
-set(CMAKE_EXECUTABLE_SUFFIX_ASM     ".elf")
-set(CMAKE_EXECUTABLE_SUFFIX_C       ".elf")
-set(CMAKE_EXECUTABLE_SUFFIX_CXX     ".elf")
-
+set(CMAKE_SYSTEM_NAME               Generic)
+set(CMAKE_SYSTEM_PROCESSOR          arm)
+
+# Some default GCC settings
+# arm-none-eabi- must be part of path environment
+set(TOOLCHAIN_PREFIX                arm-none-eabi-)
+set(C_FLAGS                         "-fdata-sections -ffunction-sections --specs=nano.specs -Wl,--gc-sections")
+set(CPP_FLAGS                       "-fno-rtti -fno-exceptions -fno-threadsafe-statics")
+
+# Define compiler settings
+set(CMAKE_C_COMPILER                ${TOOLCHAIN_PREFIX}gcc ${C_FLAGS})
+set(CMAKE_ASM_COMPILER              ${CMAKE_C_COMPILER})
+set(CMAKE_CXX_COMPILER              ${TOOLCHAIN_PREFIX}g++ ${C_FLAGS} ${CPP_FLAGS})
+set(CMAKE_OBJCOPY                   ${TOOLCHAIN_PREFIX}objcopy)
+set(CMAKE_SIZE                      ${TOOLCHAIN_PREFIX}size)
+
+set(CMAKE_EXECUTABLE_SUFFIX_ASM     ".elf")
+set(CMAKE_EXECUTABLE_SUFFIX_C       ".elf")
+set(CMAKE_EXECUTABLE_SUFFIX_CXX     ".elf")
+
 set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
\ No newline at end of file