diff --git a/lib/led_ws2812b.c b/lib/led_ws2812b.c
index 80c83f9..5641b8e 100644
--- a/lib/led_ws2812b.c
+++ b/lib/led_ws2812b.c
@@ -17,6 +17,7 @@
  *  @author King Kévin <kingkevin@cuvoodoo.info>
  *  @date 2016
  *  @note peripherals used: SPI @ref led_ws2812b_spi, timer @ref led_ws2812b_timer, DMA @ref led_ws2812b_dma
+ *  @todo improve ws2812b_set_rgb speed
  */
 
 /* standard libraries */
diff --git a/lib/usart.c b/lib/usart.c
index 86fa623..93df25d 100644
--- a/lib/usart.c
+++ b/lib/usart.c
@@ -17,6 +17,7 @@
  *  @author King Kévin <kingkevin@cuvoodoo.info>
  *  @date 2016
  *  @note peripherals used: USART @ref usart
+ *  @todo fix ring buffer racing (interrupt vs software)
  */
 
 /* standard libraries */