diff --git a/pyproject.toml b/pyproject.toml
index 501829c18..842a2b962 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,7 @@
 [build-system]
 requires = ["setuptools", "cython"]
 build-backend = "setuptools.build_meta"
+backend-path = [ "" ]
 
 [project]
 name = "xpra"