[AI-FSSDK] prepare for release javascript-sdk v6.4.0 (#1149)

Co-authored-by: Raju Ahmed <raju.ahmed@optimizely.com>

Author: jaeopt

CHANGELOG.md

@@ -5,6 +5,22 @@ 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).
 
+## [6.4.0] - May 7, 2026
+
+### New Features
+
+**Feature Rollout**: Added support for Feature Rollouts, a new experiment type
+combining Targeted Delivery simplicity with A/B test measurement capabilities.
+Feature Rollouts enable progressive rollouts with full impact analytics, metric tracking,
+and confidence intervals.
+See [Feature Rollout docs](https://support.optimizely.com/hc/en-us/articles/45552846481037-Run-Feature-Rollouts-in-Feature-Experimentation) for more information.
+
+- Add Feature Rollout support ([#1140](https://github.com/optimizely/javascript-sdk/pull/1140))
+
+### Bug Fixes
+- Export `UserProfileServiceAsync` type
+
+
 ## [6.3.1] - January 26, 2026
 
 ### Changed

lib/export_types.ts

@@ -95,6 +95,7 @@ export type {
   Event,
   DatafileOptions,
   UserProfileService,
+  UserProfileServiceAsync,
   UserProfile,
   ListenerPayload,
   OptimizelyDecision,

lib/index.browser.tests.js

@@ -153,7 +153,7 @@ describe('javascript-sdk (Browser)', function() {
         });
 
         assert.instanceOf(optlyInstance, Optimizely);
-        assert.equal(optlyInstance.clientVersion, '6.3.1');
+        assert.equal(optlyInstance.clientVersion, '6.4.0');
       });
 
       it('should set the JavaScript client engine and version', function() {

lib/index.node.tests.js

@@ -88,7 +88,7 @@ describe('optimizelyFactory', function() {
         });
 
         assert.instanceOf(optlyInstance, Optimizely);
-        assert.equal(optlyInstance.clientVersion, '6.3.1');
+        assert.equal(optlyInstance.clientVersion, '6.4.0');
       });
       // TODO: user will create and inject an event processor
       // these tests will be refactored accordingly

lib/index.react_native.spec.ts

@@ -92,7 +92,7 @@ describe('javascript-sdk/react-native', () => {
         expect(optlyInstance).toBeInstanceOf(Optimizely);
         // eslint-disable-next-line @typescript-eslint/ban-ts-comment
         // @ts-ignore
-        expect(optlyInstance.clientVersion).toEqual('6.3.1');
+        expect(optlyInstance.clientVersion).toEqual('6.4.0');
       });
 
       it('should set the React Native JS client engine and javascript SDK version', () => {

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 = '6.3.1';
+export const CLIENT_VERSION = '6.4.0';
 
 /*
  * Represents the source of a decision for feature management. When a feature

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "@optimizely/optimizely-sdk",
-  "version": "6.3.1",
+  "version": "6.4.0",
   "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",