diff --git a/esptool.py b/esptool.py
index d1d62b410..a787086b1 100755
--- a/esptool.py
+++ b/esptool.py
@@ -57,7 +57,7 @@
         raise
 
 
-__version__ = "3.3.3"
+__version__ = "3.3.4-dev"
 
 MAX_UINT32 = 0xffffffff
 MAX_UINT24 = 0xffffff