[FSSDK-13110] patch release

Author: junaed-optimizely

CHANGELOG.md

@@ -5,6 +5,14 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [6.6.1] - September 18, 2026
+
+### Bug Fixes
+- Use a versioned datafile cache key so the SDK no longer reads a stale or malformed datafile persisted by an older SDK version ([#1175](https://github.com/optimizely/javascript-sdk/pull/1175))
+
+### Changed
+- Refactor cache and event store to operate on serialized string values, centralizing JSON serialization in the prefix stores ([#1175](https://github.com/optimizely/javascript-sdk/pull/1175))
+
 ## [6.6.0] - September 3, 2026
 
 ### New Features

lib/utils/enums/index.ts

@@ -44,7 +44,7 @@ export const CONTROL_ATTRIBUTES = {
 export const JAVASCRIPT_CLIENT_ENGINE = 'javascript-sdk';
 export const NODE_CLIENT_ENGINE = 'node-sdk';
 export const REACT_NATIVE_JS_CLIENT_ENGINE = 'react-native-js-sdk';
-export const CLIENT_VERSION = '6.6.0';
+export const CLIENT_VERSION = '6.6.1';
 
 /*
  * Represents the source of a decision for feature management. When a feature

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "@optimizely/optimizely-sdk",
-  "version": "6.6.0",
+  "version": "6.6.1",
   "description": "JavaScript SDK for Optimizely Feature Experimentation, Optimizely Full Stack (legacy), and Optimizely Rollouts",
   "main": "./dist/index.node.min.js",
   "browser": "./dist/index.browser.es.min.js",