Optimizely will be sunsetting Full Stack Experimentation on July 29, 2024. See the recommended Feature Experimentation migration timeline and documentation.

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These docs are for v2.0. Click to read the latest docs for v3.0.


Optimizely Full Stack is an experimentation and feature flagging platform for websites, mobile apps, chatbots, APIs, smart devices, and anything else with a network connection. You can deploy code behind feature flags, experiment with A/B tests, and rollout or rollback features immediately. All of this functionality is available with zero performance impact via easy-to-use SDKs.

Supported functionality

Our SDKs are built for developers, and support:

  • Feature flags and experimentation – Our SDK framework natively integrates feature flags and product experimentation, so you can continuously iterate, roll features out, and roll them back.
  • Remote configuration – Update experiments in real time without a code deploy. Toggle features on and off, or change configuration variables.
  • No latency – In-memory bucketing means no blocking network requests. Test in performance-critical code paths, secure environments, and more.
  • Real-time resultsOptimizely's Stats Engine provides best-in-class statistical modeling and immediate, trustable results without waiting for long, manual data queries.
  • Cross-platform experimentation – Run server-side or client-side, on any connected device—mobile apps, websites, TV apps—with consistent bucketing across different languages.

Get started

Learn more about major concepts in Full Stack or jump into creating your first experiment:

  1. Install the SDK and customize it for your application.
  2. Get the datafile for low-latency data sharing.
  3. Instantiate an Optimizely Client in your code. If you're using a mobile platform, initialize a mobile SDK.
  4. Define feature flags that you'll use to roll out features or run feature tests.
  5. Use your feature flag to run feature tests without deploying code, or run a standalone A/B test. Choose user IDs, target with attributes, track events, and preview experiment variations.
  6. Analyze the results of your experiment.

See the API Reference for details about each API method, such as required arguments, return values, and side effects.



To build a broad experimentation program across technical and less-technical teams, pair Full Stack with Optimizely Web to integrate server-side and client-side experimentation in a single platform. For more information, see our support article Experiment end-to-end with Optimizely Web and Full Stack.

If you have any questions, please contact Support. We will be happy to help you set up any of our SDKs!