diff --git a/pyproject.toml b/pyproject.toml
index 733fbcc..fc6157a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -51,7 +51,7 @@ dashboard = ["streamlit>=1.60"]
 # Data downloads. Isolated so tests can run fully offline.
 yahoo = ["yfinance>=0.2.40"]
 # Optional analytical accelerators for advanced parameter search/ML strategies.
-extra = ["scikit-learn>=1.4", "optuna>=3.5"]
+extra = ["scikit-learn>=1.9.0", "optuna>=3.5"]
 dev = [
     "pytest>=8.0",
     "pytest-cov>=4.1",