diff --git a/pyproject.toml b/pyproject.toml
index 0e472df..095c9bc 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -35,5 +35,6 @@ features = ["pyo3/extension-module"]
 [project.optional-dependencies]
 test = [
     "pytest>=7.0",
-    "toml>=0.10"
+    "toml>=0.10",
+    "scipy"
 ]