diff --git a/pyproject.toml b/pyproject.toml
index b0f197c..40fc840 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -26,7 +26,7 @@ connected-components-3d = "^3.12.3"
 scipy = "^1.7.0"
 rich = "^13.6.0"
 scikit-image = "^0.22.0"
-ruamel.yaml = "0.18.6"
+"ruamel.yaml" = "^0.18.6"
 
 [tool.poetry.dev-dependencies]
 pytest = "^6.2.5"