diff --git a/pyproject.toml b/pyproject.toml
index 9d6fa2a..2af1e8a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,7 +34,7 @@ Issues = "https://github.com/bemserver/bemserver-api-client/issues"
 Source = "https://github.com/bemserver/bemserver-api-client"
 
 [build-system]
-requires = ["flit_core<4"]
+requires = ["flit_core<5"]
 build-backend = "flit_core.buildapi"
 
 [tool.flit.sdist]