diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index 69a2fb4e..c82a180d 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -1,5 +1,9 @@
 # RELEASE NOTES
 
+## Version 0.5.5
+
+* Upgrade sklearn > 1.6
+
 ## Version 0.5.4
 
 * Update to partial fit to respect validation data
diff --git a/pyproject.toml b/pyproject.toml
index 3da3b53c..08133517 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "ngboost"
-version = "0.5.4dev"
+version = "0.5.5dev"
 description = "Library for probabilistic predictions via gradient boosting."
 authors = ["Stanford ML Group <avati@cs.stanford.edu>"]
 readme = "README.md"