diff --git a/source/dune-project b/source/dune-project
index 067251bc729..7d67c28e579 100644
--- a/source/dune-project
+++ b/source/dune-project
@@ -1,4 +1,4 @@
-(lang dune 2.8)
+(lang dune 3.4)
 
 (name pyre)