diff --git a/CHANGES.txt b/CHANGES.txt
index 4dbca39..59891fc 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -2,6 +2,7 @@
  - Added support for synchronizing feature flags with rule-based segments. These segments determine membership at runtime by evaluating their configured rules against the user attributes provided to the SDK.
  - Added support for synchronizing feature flags with prerequisites. This allows customers to define dependency conditions between flags, which are evaluated before any allowlists or targeting rules.
  - Added support for synchronizing SDK impressions with properties.
+ - Added support for the new impressions tracking toggle available on feature flags.
  - Added `sync.requestOptions.getHeaderOverrides` configuration option to enhance Synchronizer HTTP request Headers for Authorization Frameworks.
  - Updated @splitsoftware/splitio-commons package to version 2.3.0 and some transitive dependencies for vulnerability fixes and other improvements.
  - BREAKING CHANGES:
diff --git a/types/index.d.ts b/types/index.d.ts
index cc349e5..9502f85 100644
--- a/types/index.d.ts
+++ b/types/index.d.ts
@@ -2,246 +2,194 @@
 // Project: https://www.split.io/
 // Definitions by: Emiliano Sanchez <https://github.com/EmilianoSanchez/>
 
+import '@splitsoftware/splitio-commons';
 import { RequestOptions } from 'http';
 
-export = JsSyncTools;
-
-declare module JsSyncTools {
+/**
+ * JavaScript synchronizer tool.
+ *
+ * @see {@link https://help.split.io/hc/en-us/articles/4421513571469-Split-JavaScript-synchronizer-tools}.
+ */
+export class Synchronizer {
   /**
-   * JavaScript synchronizer tool.
+   * Creates a new Synchronizer instance
    *
-   * @see {@link https://help.split.io/hc/en-us/articles/4421513571469-Split-JavaScript-synchronizer-tools}.
+   * @param config - The synchronizer config object
    */
-  export class Synchronizer {
-    /**
-     * Creates a new Synchronizer instance
-     *
-     * @param config - The synchronizer config object
-     */
-    constructor(config: ISynchronizerSettings);
-    /**
-     * Execute synchronization
-     *
-     * @param cb - Optional error-first callback to be invoked when the synchronization ends. The callback will be invoked with an error as first argument if the synchronization fails.
-     * @returns A promise that resolves when the operation ends, with a boolean indicating if operation succeeded or not. The promise never rejects.
-     */
-    execute(cb?: (err?: Error) => void): Promise<boolean>;
-    // @TODO expose settings eventually
-    // settings: ISettings
-  }
-
+  constructor(config: ISynchronizerSettings);
   /**
-   * Log levels.
+   * Execute synchronization
+   *
+   * @param cb - Optional error-first callback to be invoked when the synchronization ends. The callback will be invoked with an error as first argument if the synchronization fails.
+   * @returns A promise that resolves when the operation ends, with a boolean indicating if operation succeeded or not. The promise never rejects.
    */
-  type LogLevel = 'DEBUG' | 'INFO' | 'WARN' | 'ERROR' | 'NONE';
+  execute(cb?: (err?: Error) => void): Promise<boolean>;
+  // @TODO expose settings eventually
+  // settings: ISettings
+}
+
+/**
+ * Settings interface for Synchronizer instances.
+ *
+ * @see {@link https://help.split.io/hc/en-us/articles/4421513571469-Split-JavaScript-synchronizer-tools#configuration}
+ */
+export interface ISynchronizerSettings {
   /**
-   * Available URL settings for the synchronizer.
+   * Core settings.
    */
-  type UrlSettings = {
-    /**
-     * String property to override the base URL where the synchronizer will get feature flagging related data like a feature flag rollout plan or segments information.
-     *
-     * @defaultValue `'https://sdk.split.io/api'`
-     */
-    sdk?: string
+  core: {
     /**
-     * String property to override the base URL where the synchronizer will post impressions and events.
+     * Your SDK key.
      *
-     * @defaultValue `'https://events.split.io/api'`
+     * @see {@link https://help.split.io/hc/en-us/articles/360019916211-API-keys}
      */
-    events?: string,
-    /**
-     * String property to override the base URL where the synchronizer will post telemetry data.
-     *
-     * @defaultValue `'https://telemetry.split.io/api'`
-     */
-    telemetry?: string
-  };
-
-  /**
-   * SplitFilter type.
-   */
-  type SplitFilterType = 'byName' | 'bySet';
+    authorizationKey: string
+  }
   /**
-   * Defines a feature flag filter, described by a type and list of values.
+   * Defines which kind of storage we should instantiate.
    */
-  interface SplitFilter {
+  storage: {
+    /**
+     * Storage type. The only possible value is `'PLUGGABLE'`, which is the default.
+     */
+    type?: 'PLUGGABLE',
     /**
-     * Type of the filter.
+     * A valid storage instance.
      */
-    type: SplitFilterType,
+    wrapper: Object
     /**
-     * List of values: feature flag names for 'byName' filter type, and feature flag name prefixes for 'byPrefix' type.
+     * Optional prefix added to the storage keys to prevent any kind of data collision between SDK versions.
+     *
+     * @defaultValue `'SPLITIO'`
      */
-    values: string[],
+    prefix?: string
   }
   /**
-   * ImpressionsMode type.
+   * List of URLs that the Synchronizer will use as base for it's synchronization functionalities.
+   * Do not change these settings unless you're working an advanced use case, like connecting to a proxy.
    */
-  type ImpressionsMode = 'OPTIMIZED' | 'DEBUG';
+  urls?: SplitIO.UrlSettings
   /**
-   * Settings interface for Synchronizer instances.
+   * Boolean value to indicate whether the logger should be enabled or disabled by default, or a log level string.
+   *
+   * Examples:
+   * ```
+   * config.debug = true
+   * config.debug = 'WARN'
+   * ```
    *
-   * @see {@link https://help.split.io/hc/en-us/articles/4421513571469-Split-JavaScript-synchronizer-tools#configuration}
+   * @defaultValue `false`
    */
-  interface ISynchronizerSettings {
-    /**
-     * Core settings.
-     */
-    core: {
-      /**
-       * Your SDK key.
-       *
-       * @see {@link https://help.split.io/hc/en-us/articles/360019916211-API-keys}
-       */
-      authorizationKey: string
-    }
+  debug?: boolean | SplitIO.LogLevel
+  /**
+   * Synchronization settings.
+   */
+  sync?: {
     /**
-     * Defines which kind of storage we should instantiate.
+     * List of feature flag filters. These filters are used to fetch a subset of the feature flag definitions in your environment.
+     *
+     * Example:
+     * ```
+     * splitFilter: [
+     *   { type: 'byName', values: ['my_feature_flag_1', 'my_feature_flag_2'] }, // will fetch feature flags named 'my_feature_flag_1' and 'my_feature_flag_2'
+     * ]
+     * ```
      */
-    storage: {
-      /**
-       * Storage type. The only possible value is `'PLUGGABLE'`, which is the default.
-       */
-      type?: 'PLUGGABLE',
-      /**
-       * A valid storage instance.
-       */
-      wrapper: Object
-      /**
-       * Optional prefix added to the storage keys to prevent any kind of data collision between SDK versions.
-       *
-       * @defaultValue `'SPLITIO'`
-       */
-      prefix?: string
-    }
+    splitFilters?: SplitIO.SplitFilter[]
     /**
-     * List of URLs that the Synchronizer will use as base for it's synchronization functionalities.
-     * Do not change these settings unless you're working an advanced use case, like connecting to a proxy.
+     * Feature Flag Spec version. Option to determine which version of the feature flag definitions are fetched and stored.
+     * Possible values are `'1.0'`, `'1.1'`, `'1.2'`, and `'1.3'`.
+     *
+     * @defaultValue `'1.3'`
      */
-    urls?: UrlSettings
+    flagSpecVersion?: '1.0' | '1.1' | '1.2' | '1.3'
     /**
-     * Boolean value to indicate whether the logger should be enabled or disabled by default, or a log level string.
+     * Impressions Collection Mode. Option to determine how impressions are going to be sent to Split Servers.
      *
-     * Examples:
-     * ```
-     * config.debug = true
-     * config.debug = 'WARN'
-     * ```
+     * Possible values are `'DEBUG'` and `'OPTIMIZED'`.
+     * - DEBUG: will send all the impressions generated (recommended only for debugging purposes).
+     * - OPTIMIZED: will send unique impressions to Split Servers avoiding a considerable amount of traffic that duplicated impressions could generate.
      *
-     * @defaultValue `false`
+     * @defaultValue `'OPTIMIZED'`
      */
-    debug?: boolean | LogLevel
+    impressionsMode?: SplitIO.ImpressionsMode
     /**
-     * Synchronization settings.
+     * Custom options object for HTTP(S) requests in Node.js.
+     * If provided, this object is merged with the options object passed for Node-Fetch calls.
+     *
+     * @see {@link https://www.npmjs.com/package/node-fetch#options}
      */
-    sync?: {
+    requestOptions?: {
       /**
-       * List of feature flag filters. These filters are used to fetch a subset of the feature flag definitions in your environment.
+       * Custom function called before each request, allowing you to add or update headers in Synchronizer HTTP requests.
+       * Some headers, such as `SplitSDKVersion`, are required by the Synchronizer and cannot be overridden.
+       * To pass multiple headers with the same name, combine their values into a single line, separated by commas. Example: `{ 'Authorization': 'value1, value2' }`
+       * Or provide keys with different cases since headers are case-insensitive. Example: `{ 'authorization': 'value1', 'Authorization': 'value2' }`
+       *
+       * @defaultValue `undefined`
        *
-       * Example:
+       * @param context - The context for the request, which contains the `headers` property object representing the current headers in the request.
+       * @returns An object representing a set of headers to be merged with the current headers.
+       *
+       * @example
        * ```
-       * splitFilter: [
-       *   { type: 'byName', values: ['my_feature_flag_1', 'my_feature_flag_2'] }, // will fetch feature flags named 'my_feature_flag_1' and 'my_feature_flag_2'
-       * ]
+       * const getHeaderOverrides = (context) => {
+       *   return {
+       *     'Authorization': context.headers['Authorization'] + ', other-value',
+       *     'custom-header': 'custom-value'
+       *   };
+       * };
        * ```
        */
-      splitFilters?: SplitFilter[]
+      getHeaderOverrides?: (context: { headers: Record<string, string> }) => Record<string, string>;
       /**
-       * Feature Flag Spec version. Option to determine which version of the feature flag definitions are fetched and stored.
-       * Possible values are `'1.0'`, `'1.1'`, `'1.2'`, and `'1.3'`.
+       * Custom Node.js HTTP(S) Agent used for HTTP(S) requests.
        *
-       * @defaultValue `'1.3'`
-       */
-      flagSpecVersion?: '1.0' | '1.1' | '1.2' | '1.3'
-      /**
-       * Impressions Collection Mode. Option to determine how impressions are going to be sent to Split Servers.
+       * You can use it, for example, for certificate pinning or setting a network proxy:
        *
-       * Possible values are `'DEBUG'` and `'OPTIMIZED'`.
-       * - DEBUG: will send all the impressions generated (recommended only for debugging purposes).
-       * - OPTIMIZED: will send unique impressions to Split Servers avoiding a considerable amount of traffic that duplicated impressions could generate.
-       *
-       * @defaultValue `'OPTIMIZED'`
-       */
-      impressionsMode?: ImpressionsMode
-      /**
-       * Custom options object for HTTP(S) requests in Node.js.
-       * If provided, this object is merged with the options object passed for Node-Fetch calls.
+       * ```
+       * const { HttpsProxyAgent } = require('https-proxy-agent');
        *
-       * @see {@link https://www.npmjs.com/package/node-fetch#options}
-       */
-      requestOptions?: {
-        /**
-         * Custom function called before each request, allowing you to add or update headers in Synchronizer HTTP requests.
-         * Some headers, such as `SplitSDKVersion`, are required by the Synchronizer and cannot be overridden.
-         * To pass multiple headers with the same name, combine their values into a single line, separated by commas. Example: `{ 'Authorization': 'value1, value2' }`
-         * Or provide keys with different cases since headers are case-insensitive. Example: `{ 'authorization': 'value1', 'Authorization': 'value2' }`
-         *
-         * @defaultValue `undefined`
-         *
-         * @param context - The context for the request, which contains the `headers` property object representing the current headers in the request.
-         * @returns An object representing a set of headers to be merged with the current headers.
-         *
-         * @example
-         * ```
-         * const getHeaderOverrides = (context) => {
-         *   return {
-         *     'Authorization': context.headers['Authorization'] + ', other-value',
-         *     'custom-header': 'custom-value'
-         *   };
-         * };
-         * ```
-         */
-        getHeaderOverrides?: (context: { headers: Record<string, string> }) => Record<string, string>;
-        /**
-         * Custom Node.js HTTP(S) Agent used for HTTP(S) requests.
-         *
-         * You can use it, for example, for certificate pinning or setting a network proxy:
-         *
-         * ```
-         * const { HttpsProxyAgent } = require('https-proxy-agent');
-         *
-         * const proxyAgent = new HttpsProxyAgent(process.env.HTTPS_PROXY || 'http://10.10.1.10:1080');
-         *
-         * const synchronizer = Synchronizer({
-         *   ...
-         *   sync: {
-         *     requestOptions: {
-         *       agent: proxyAgent
-         *     }
-         *   }
-         * })
-         * ```
-         *
-         * @see {@link https://nodejs.org/api/https.html#class-httpsagent}
-         *
-         * @defaultValue `undefined`
-         */
-        agent?: RequestOptions['agent']
-      },
-    }
-    /**
-     * Scheduler settings.
-     */
-    scheduler?: {
-      /**
-       * Maximum number of impressions to send per POST request.
+       * const proxyAgent = new HttpsProxyAgent(process.env.HTTPS_PROXY || 'http://10.10.1.10:1080');
        *
-       * @defaultValue `1000`
-       */
-      impressionsPerPost?: number
-      /**
-       * Maximum number of events to send per POST request.
+       * const synchronizer = Synchronizer({
+       *   ...
+       *   sync: {
+       *     requestOptions: {
+       *       agent: proxyAgent
+       *     }
+       *   }
+       * })
+       * ```
        *
-       * @defaultValue `1000`
-       */
-      eventsPerPost?: number
-      /**
-       * Maximum number of retry attempts for posting impressions and events.
+       * @see {@link https://nodejs.org/api/https.html#class-httpsagent}
        *
-       * @defaultValue `3`
+       * @defaultValue `undefined`
        */
-      maxRetries?: number
-    }
+      agent?: RequestOptions['agent']
+    },
+  }
+  /**
+   * Scheduler settings.
+   */
+  scheduler?: {
+    /**
+     * Maximum number of impressions to send per POST request.
+     *
+     * @defaultValue `1000`
+     */
+    impressionsPerPost?: number
+    /**
+     * Maximum number of events to send per POST request.
+     *
+     * @defaultValue `1000`
+     */
+    eventsPerPost?: number
+    /**
+     * Maximum number of retry attempts for posting impressions and events.
+     *
+     * @defaultValue `3`
+     */
+    maxRetries?: number
   }
 }