diff --git a/Improving-performance-with-Viper-code.md b/Improving-performance-with-Viper-code.md
index 172cd2e..d44553c 100644
--- a/Improving-performance-with-Viper-code.md
+++ b/Improving-performance-with-Viper-code.md
@@ -1,7 +1,7 @@
 The viper code emitter uses special viper native data types to get faster performance. The largest advantage is for integer arithmetic, bit manipulations and integer array operations. 
 
 
-Read the official documentation here: https://docs.micropython.org/en/v1.9.3/pyboard/reference/speed_python.html
+Read the official documentation here: https://docs.micropython.org/en/latest/reference/speed_python.html
 
 # An example
 ```py