---
title: 2024 Feature Experimentation release notes
slug: feature-experimentation/release-notes/2024-optimizely-feature-experimentation-release-notes
docTags: 
createdAt: 2026-07-20T15:44:36.944Z
---

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- Optimizely Feature Experimentation

## December

Released [event properties](docId:3kGIZlCkODJIOJuT3bdWo), which let you attach additional information to an event to all customers.

## November

Released [Custom Flags Dashboard](docId\:uK1k1V4L8vrVFgur_AY_u) to all customers.

## October

- Released [Custom Flags Dashboard](docId\:uK1k1V4L8vrVFgur_AY_u) to beta. 
- Released event properties to open beta. See [event properties](docId:3kGIZlCkODJIOJuT3bdWo).

## September

- Released [Optimizely Reporting for Experimentation](docId\:YWh1V46NbUVu2h0Wjy3zH), providing you with dashboards and reports that show key metrics such as experiment velocity, conclusive rate, win rate, and uplift.
- Updated the **Event Key** text field to automatically populate with the **Event Name** formatted in lowercase, replacing any non-alphanumeric characters with underscores. See [Create an event in Optimizely Feature Experimentation using the UI](docId\:v2goO-UxyIA4AtTSR-h-9).

## August

- Began rolling out [Flag Lifecycle Management](docId\:Bog7o25N6pDj3-2qpsVGn) to customers, which helps you view the state of your experiments and targeted deliveries. See [Manage flags](docId\:F8tdFPnxECabBXsQkBqDt) and [Manage rules](docId\:zfzSgUawnKhGc59SYlTbL).
- Released [granular roles and permissions](docId\:VfzalP5Ep4rqE-gTd6p7m), which gives you fine-grained access control of the entities in your projects.
- Released event properties to beta. Event properties let you filter a created event in Optimizely’s UI based on additional information you have attached to it. When you send events, you can add information about the product or action performed to create a more specific metric when using the event in the experiment results. Contact your Customer Success Manager or [sign up for the beta on Optimizely.com](https://www.optimizely.com/beta). See [event properties](docId:3kGIZlCkODJIOJuT3bdWo).

## July

Renamed the following [Optimizely REST API](docId\:CwbqaxvWjxN8pwcorN55w) endpoints to clarify they archive the entities instead of deleting them:

- [Archive custom event](docId\:hwqs8hLHyNBajzg7ooxSt).
- [Archive an attribute](docId\:fZEqVJpCTjRrc07m5jxro).

Feature Experimentation REST API enhancements

- **Added variations and metrics to the response for the**[ List Rules](docId\:nV9i0xt5kQyLKIp1gPT4U)** endpoint – **The [\`/rules\`](docId\:nV9i0xt5kQyLKIp1gPT4U) endpoint now returns high-level information on variations for flag rules and metrics for A/B tests and multi-armed bandits. For example,

```javascript
{
        "name": "Repeat Buyers Test",

        // ...

        "variations": {
            "off": {
                "key": "off",
                "name": "Off",
                "percentage_included": 3333,
                "variation_id": 329457
            },
            "repeat_buyers_1": {
                "key": "repeat_buyers_1",
                "name": "Repeat Buyers 1",
                "percentage_included": 3333,
                "variation_id": 373838
            },
            "repeat_buyers_2": {
                "key": "repeat_buyers_2",
                "name": "Repeat Buyers 2",
                "percentage_included": 3334,
                "variation_id": 373839
            }
        },
        "metrics": [
            {
                "event_id": 27053200523,
                "scope": "visitor",
                "aggregator": "unique",
                "winning_direction": "increasing",                 
                "display_title": "addToCart"
            },
            {
                "scope": "visitor",
                "aggregator": "sum",
                "winning_direction": "increasing",
                "display_title": "Overall Revenue"
            }
       ]
}
    
```

- **Updated the API response for the **[List Reports](docId:-X_h8nD684BQUD_yOjgJC)** endpoint** – The **revision** field was previously documented in the API reference but not actually returned by the API. The API response was updated to return the **revision** field.
- **Updated documentation for layer\_experiment\_id **– The following API endpoints return the **layer\_experiment\_id** field, but it was not consistently documented. Updated the [Feature Experimentation API reference](docId\:CDe1sxqw6YnEHi5bbQrh2) to ensure consistency with actual API behavior.
  - [Fetch the Rule for a Ruleset in an Environment](docId\:YYvzC4lOorCtWiVhPKMmL)
  - [List Rules](docId\:nV9i0xt5kQyLKIp1gPT4U)
  - [Fetch a Rule for a specific experiment\\\_id](docId\:E7_P_8NWk9Wh3k19PMZtE)

## June

- Released the ability to sign up for email notifications when Optimizely Experimentation detects a [sample ratio mismatch](docId\:JFKBHyB1tPQH0-EMRjAOR) in your running experiments. See[ Enable email notifications in Optimizely Experimentation](docId\:BU9xpaNSi4fHfBQ36bOdr).
- Updated the [\`/reports endpoint\`](docId:-X_h8nD684BQUD_yOjgJC) to return tokens for pagination of results as a stand-alone element (previously only included in URLs in response). This makes it easier to programmatically form URLs to request reports from other pages. 
  - Also updated the `/reports` endpoint to return valid endpoints for `fetch_results_api_url` and `fetch_results_ui_url` to fetch experiment results with subsequent API calls.
- Released lifecycle management for flags and rules to open beta. This introduces new statutes and makes it easier to see the state of your experiments. See [Manage flags](docId\:F8tdFPnxECabBXsQkBqDt) and [Manage rules](docId\:zfzSgUawnKhGc59SYlTbL).

## May

- Released the ability to use cross-project events to track events from your Optimizely Web Experimentation projects in your Optimizely Feature Experimentation project. See [Cross-project events](docId\:ZL_1cekoRgYONCLUBrv5b).
- Launched automatic creation of flag [variables](docId\:eH-UMm_rOn_GdGDGLV6__) by brainstorming using Optimizely Agent Platform. 
- Renamed and released Advanced Audience Targeting to [Real-Time Segments for Feature Experimentation](docId:6UBBxxRv331nBIVZ2lun8). This lets you use [Optimizely Data Platform (ODP) real-time segments](docId:7-qDl01uxXDPl5_jFVF1E) to build your Feature Experimentation audiences.
- Updated the minimum SDK versions required for migration from Full Stack (Legacy) to Feature Experimentation. See [Upgrade to Optimizely Feature Experimentation from Optimizely Full Stack](docId\:X7Q2_koHvW5p0qK1aY8QV).
  - Java SDK version 3.6+.
  - Android SDK version 3.7+.
  - No other SDKs have minimum versions.
- Launched automatic creation of [flag variations](docId\:nmipY0LAkbpzTcsggjlPn) by brainstorming using Optimizely Agent Platform.

## April

Released the ability to [link a hypothesis in Collaboration with an experiment in Optimizely Feature Experimentation](docId:8eUXWAQfU8Hhv18zHSrmS).

## March

Released the ability to use[ bucketing IDs ](docId\:oMDqV-N-b4JV5UbYHsfmq)to decouple user bucketing from user identification.  

## February

- Increased the allowlist total from 10 to 50 users.
- Released the [Scheduling API](docId\:J1ie3gX0PpvkjVkLq6dU6), which lets you list, create, update, and delete [scheduled changes](docId\:p46i-zfIwefbf8noQwHhr) for your Feature Experimentation flags and rules.

## January 

### Breaking change for SDKs

Released a [major version](https://semver.org) update for the following SDKs. See the SDK's GitHub release notes for details, including breaking changes.

- [Agent](https://github.com/optimizely/agent/releases/tag/v4.0.0) – v4.0.0
- [Android SDK](https://github.com/optimizely/android-sdk/releases/tag/4.0.0) – v4.0.0
- [C# SDK](https://github.com/optimizely/csharp-sdk/releases/tag/v4.0.0) – v4.0.0
- [Go SDK](https://github.com/optimizely/go-sdk/releases/tag/v2.0.0) – v2.0.0
- [Java SDK](https://github.com/optimizely/java-sdk/releases/tag/4.0.0) – v4.0.0
- [JavaScript (Browser and Node) SDK](https://github.com/optimizely/javascript-sdk/releases) – 5.0.0
- [Python SDK](https://github.com/optimizely/python-sdk/releases/tag/5.0.0) – 5.0.0
- [React SDK](https://github.com/optimizely/react-sdk/releases/tag/3.0.0) – 3.0.0
- [React Native SDK](https://github.com/optimizely/react-sdk/blob/master/src/client.ts) – 3.0.0
- [Ruby SDK](https://github.com/optimizely/ruby-sdk/releases/tag/v5.0.0) – 4.0.0
- [Swift SDK](https://github.com/optimizely/swift-sdk/releases/tag/v4.0.0) – 4.0.0

The release includes [Advanced Audience Targeting](docId:6UBBxxRv331nBIVZ2lun8), which was renamed to Real-Time Segments for Feature Experimentation in [May 2024](docId\:X7Q2_koHvW5p0qK1aY8QV).