diff --git a/spine-flutter/CHANGELOG.md b/spine-flutter/CHANGELOG.md
index c93d8ac1a..9776f19b6 100644
--- a/spine-flutter/CHANGELOG.md
+++ b/spine-flutter/CHANGELOG.md
@@ -1,3 +1,6 @@
+# 4.2.31
+- Fix bug in IKConstraint leading to NaNs.
+
 # 4.2.30
 - Switch to spine-cpp SkeletonRenderer
 
diff --git a/spine-flutter/pubspec.yaml b/spine-flutter/pubspec.yaml
index 76b141369..5856fd261 100644
--- a/spine-flutter/pubspec.yaml
+++ b/spine-flutter/pubspec.yaml
@@ -1,6 +1,6 @@
 name: spine_flutter
 description: The official Spine Flutter Runtime to load, display and interact with Spine animations.
-version: 4.2.30
+version: 4.2.31
 homepage: https://esotericsoftware.com
 repository: https://github.com/esotericsoftware/spine-runtimes
 issue_tracker: https://github.com/esotericsoftware/spine-runtimes/issues