diff --git a/pyproject.toml b/pyproject.toml
index 108c33c9..447f8410 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -91,6 +91,7 @@ notes = """,
 python_paths = "./"
 testpaths = "tests/"
 addopts = "-vv --doctest-modules -p no:warnings --ignore-glob='*mock*'"
+[build-system]
 requires = ["poetry>=0.12"]
 build-backend = "poetry.masonry.api"