diff --git a/stm-firmware/systick.c b/stm-firmware/systick.c
index a135d59..b96c245 100644
--- a/stm-firmware/systick.c
+++ b/stm-firmware/systick.c
@@ -46,7 +46,7 @@ uint64_t systick_get_global_tick()
 	return global_tick_ms;
 }
 
-bool systick_ticks_have_passed(uint64_t start_timestamp, uint64_t ticks)
+bool __attribute__((optimize("O3"))) systick_ticks_have_passed(uint64_t start_timestamp, uint64_t ticks)
 {
 	uint64_t end_timestamp = start_timestamp + ticks;
 	uint64_t current_timestamp = systick_get_global_tick();
@@ -73,7 +73,7 @@ bool systick_ticks_have_passed(uint64_t start_timestamp, uint64_t ticks)
  *
  * @warning For calling cyclic functions use separate timers/flags and don't spoil this function
  */
-void SysTick_Handler()
+void __attribute__((optimize("O3"))) SysTick_Handler()
 {
 	/* Increase tick counters */
 	wait_tick_ms++;