: Holdouts can now be configured to exclude Targeted Delivery rules, so users held out of experiments still receive their Targeted Delivery experiences. This gives you a cleaner measure of experiment impact without holding users back from ongoing rollouts.

Add holdout exclusion logic for Targeted Delivery rules (

Javascript-SDK - 6.6.1

Javascript-SDK - 6.6.0

ai_cta

ai_identity

ai_chat

ai_product


Data set that refers to a person or a role and contains at least one address via which the person or role can receive messages.

recipient

Javascript-SDK - 6.5.0

feature-experimentation-release-notes

Release Notes for Feature Experimentation

2026 Optimizely Feature Experimentation release notes

2025 Optimizely Feature Experimentation release notes

2024 Optimizely Feature Experimentation release notes

2023 Optimizely Feature Experimentation release notes

2022 Optimizely Feature Experimentation release notes

Agent

Android SDK

C# SDK

Flutter SDK

Go SDK

Java SDK

JavaScript SDK

PHP SDK

Python SDK

React SDK

Ruby SDK

Swift SDK

Feature Experimentation SDK release notes

Release notes

Feature Experimentation API changelog – 2025

Javascript-SDK - 6.6.0

[6.6.0] - September 3, 2026

New Features