diff --git a/pyproject.toml b/pyproject.toml
index 2bc0cd3..d4eb45a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,7 +21,7 @@ ipywidgets = { version = "^8.1.2", optional = true }
 traitlets = { version = "^5.14.3", optional = true }
 
 [tool.poetry.extras]
-jupyter = ["ipytree", "ipywidgets", "traitlets"]
+jupyter = ["ipytree", "ipywidgets", "traitlets","graphviz"]
 
 [tool.poetry.group.dev.dependencies]
 pytest = "^8.1.1"