diff --git a/pyproject.toml b/pyproject.toml
index ef4cf96..40fc68a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -17,7 +17,7 @@ scikit-learn = "^1.3.2"
 
 [tool.poetry.group.dev.dependencies]
 pytest = ">=7.4,<9.0"
-pytest-cov = "^4.1.0"
+pytest-cov = ">=4.1,<6.0"
 pytest-xdist = "^3.3.1"
 black = ">=23.7,<25.0"
 flake8 = ">=6.1,<8.0"