---
title: Javascript-SDK - 2.0.0
slug: feature-experimentation/release-notes/javascript-sdk-2-0-0
docTags: 
createdAt: 2026-07-20T15:44:19.169Z
---

April 11th, 2018

This major release of the Optimizely SDK introduces APIs for Feature Management. It also introduces some breaking changes listed below.

\### New Features
\* Introduces the \`isFeatureEnabled\` API to determine whether to show a feature to a user or not.
\`\`\`
var enabled = optimizelyClient.isFeatureEnabled('my\_feature\_key', 'user\_1', userAttributes);
\`\`\`

\* You can also get all the enabled features for the user by calling the following method which returns a list of strings representing the feature keys:
\`\`\`
var enabledFeatures = optimizelyClient.getEnabledFeatures('user\_1', userAttributes);
\`\`\`

\* Introduces Feature Variables to configure or parameterize your feature. There are four variable types: \`Integer\`, \`String\`, \`Double\`, \`Boolean\`.
\`\`\`
var stringVariable = optimizelyClient.getFeatureVariableString('my\_feature\_key', 'string\_variable\_key', 'user\_1');
var integerVariable = optimizelyClient.getFeatureVariableInteger('my\_feature\_key', 'integer\_variable\_key', 'user\_1');
var doubleVariable = optimizelyClient.getFeatureVariableDouble('my\_feature\_key', 'double\_variable\_key', 'user\_1');
var booleanVariable = optimizelyClient.getFeatureVariableBoolean('my\_feature\_key', 'boolean\_variable\_key', 'user\_1');
\`\`\`

\### Breaking changes
\* The \`track\` API with revenue value as a stand-alone parameter has been removed. The revenue value should be passed in as an entry of the event tags map. The key for the revenue tag is \`revenue\` and will be treated by Optimizely as the key for analyzing revenue data in results.
\`\`\`
var eventTags = \{
'revenue': 1200
};

optimizelyClient.track('event\_key', 'user\_id', userAttributes, eventTags);
\`\`\`
\* The package name has changed from \`optimizely-client-sdk\` to \`optimizely-sdk\` as we have consolidated both Node and JavaScript SDKs into one.

[https://github.com/optimizely/javascript-sdk/releases/tag/v2.0.0](https://github.com/optimizely/javascript-sdk/releases/tag/v2.0.0)