diff --git a/pyproject.toml b/pyproject.toml
index 61ca671d0..0d3affa0e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,6 +20,12 @@ exclude = ["temporalio/bridge/**/target"]
 # support this script in a subdirectory like scripts/.
 [tool.poetry.build]
 script = "build.py"
+# In https://github.com/python-poetry/poetry-core/pull/318, Poetry stopped using
+# a setup file, but we are using setuptools Rust manually in our build.py which
+# needs a setup file.
+# TODO(cretz): Find a way to not require a setup file since that is going away
+# at some point in Poetry. Revisit Maturin or fine some other approach.
+generate-setup-file = true
 
 [tool.poetry.urls]
 "Bug Tracker" = "https://github.com/temporalio/sdk-python/issues"