DataDog · BenoitZugmeyer · Aug 26, 2026 · Aug 26, 2026 · Jun 29, 2026 · Jun 30, 2026
@@ -1,5 +1,5 @@
 import type { CookieStore, CookieStoreEventMap } from '@datadog/js-core/util'
-import { monitor } from '../tools/monitor'
+import { monitor } from '@datadog/js-core/monitor'
 import { getZoneJsOriginalValue } from '../tools/getZoneJsOriginalValue'
 import { noop } from '../tools/utils/functionUtils'
 import type { VisualViewport, VisualViewportEventMap } from './browser.types'

@@ -2,9 +2,9 @@ import type { ClocksState } from '@datadog/js-core/time'
 import { clocksNow } from '@datadog/js-core/time'
 import { normalizeUrl, globalObject } from '@datadog/js-core/util'
 import type { GlobalObject } from '@datadog/js-core/util'
+import { monitorError } from '@datadog/js-core/monitor'
 import type { InstrumentedMethodCall } from '../tools/instrumentMethod'
 import { instrumentMethod } from '../tools/instrumentMethod'
-import { monitorError } from '../tools/monitor'
 import { Observable } from '../tools/observable'
 import { readBytesFromStream } from '../tools/readBytesFromStream'
 import { tryToClone } from '../tools/utils/responseUtils'

@@ -1,20 +1,11 @@
 import { globalObject } from '@datadog/js-core/util'
+import { PageExitReason } from '@datadog/js-core/transport'
+import type { PageMayExitEvent } from '@datadog/js-core/transport'
 import { Observable } from '../tools/observable'
-import { objectValues } from '../tools/utils/polyfills'
 import { addEventListeners, addEventListener, DOM_EVENT } from './addEventListener'
 
-export const PageExitReason = {
-  HIDDEN: 'visibility_hidden',
-  UNLOADING: 'before_unload',
-  PAGEHIDE: 'page_hide',
-  FROZEN: 'page_frozen',
-} as const
-
-export type PageExitReason = (typeof PageExitReason)[keyof typeof PageExitReason]
-
-export interface PageMayExitEvent {
-  reason: PageExitReason
-}
+export { PageExitReason, isPageExitReason } from '@datadog/js-core/transport'
+export type { PageMayExitEvent } from '@datadog/js-core/transport'
 
 export function createPageMayExitObservable(): Observable<PageMayExitEvent> {
   return new Observable<PageMayExitEvent>((observable) => {
@@ -54,7 +45,3 @@ export function createPageMayExitObservable(): Observable<PageMayExitEvent> {
     }
   })
 }
-
-export function isPageExitReason(reason: string): reason is PageExitReason {
-  return objectValues(PageExitReason).includes(reason as PageExitReason)
-}
@@ -1,8 +1,8 @@
 import { clocksNow } from '@datadog/js-core/time'
 import { ConsoleApiName, globalConsole } from '@datadog/js-core/util'
+import { callMonitored } from '@datadog/js-core/monitor'
 import { isError, computeRawError } from '../error/error'
 import { Observable, mergeObservables } from '../../tools/observable'
-import { callMonitored } from '../../tools/monitor'
 import { sanitize } from '../../tools/serialisation/sanitize'
 import { jsonStringify } from '../../tools/serialisation/jsonStringify'
 import type { RawError } from '../error/error.types'

@@ -1,6 +1,6 @@
+import { monitor } from '@datadog/js-core/monitor'
 import type { RawTelemetryUsage, RawTelemetryUsageFeature } from '../telemetry'
 import { addTelemetryUsage } from '../telemetry'
-import { monitor } from '../../tools/monitor'
 import type { BufferedObservable } from '../../tools/observable'
 import type { ContextManager } from './contextManager'
 import type { ContextManagerMethod, CustomerContextKey } from './contextConstants'

@@ -1,6 +1,6 @@
 import { clocksNow } from '@datadog/js-core/time'
+import { monitor } from '@datadog/js-core/monitor'
 import { toStackTraceString } from '../../tools/stackTrace/handlingStack'
-import { monitor } from '../../tools/monitor'
 import { mergeObservables, Observable } from '../../tools/observable'
 import { addEventListener, DOM_EVENT, isEventSupported } from '../../browser/addEventListener'
 import { safeTruncate } from '../../tools/utils/stringUtils'

@@ -10,6 +10,7 @@ import {
 } from '@datadog/js-core/time'
 import type { TimeStamp, RelativeTime } from '@datadog/js-core/time'
 import { isWorkerEnvironment } from '@datadog/js-core/util'
+import { monitorError } from '@datadog/js-core/monitor'
 import { Observable } from '../../tools/observable'
 import { createValueHistory } from '../../tools/valueHistory'
 import { addEventListener, addEventListeners, DOM_EVENT } from '../../browser/addEventListener'
@@ -22,7 +23,6 @@ import type { TrackingConsentState } from '../trackingConsent'
 import { display } from '../../tools/display'
 import { isSampled } from '../sampler'
 import { TelemetryMetrics, addTelemetryMetrics } from '../telemetry'
-import { monitorError } from '../../tools/monitor'
 import type { SessionState } from './sessionState'
 import {
   expandOnly,

@@ -1,3 +1,4 @@
+import { monitorError } from '@datadog/js-core/monitor'
 import { isEmptyObject } from '../../../tools/utils/objectUtils'
 import type { CookieOptions } from '../../../browser/cookie'
 import { getCookies } from '../../../browser/cookie'
@@ -8,7 +9,6 @@ import type { SessionState } from '../sessionState'
 import { toSessionString, toSessionState } from '../sessionState'
 import { Observable } from '../../../tools/observable'
 import { mockable } from '../../../tools/mockable'
-import { monitorError } from '../../../tools/monitor'
 import type { CookieAccess } from '../../../browser/cookieAccess'
 import {
   areCookiesAuthorized,

@@ -1,7 +1,7 @@
 import { createHook } from '@datadog/js-core/assembly'
 import { INTAKE_SITE_US1_FED, INTAKE_SITE_US2_FED, INTAKE_SITE_US1 } from '@datadog/js-core/transport'
+import { callMonitored } from '@datadog/js-core/monitor'
 import { NO_ERROR_STACK_PRESENT_MESSAGE } from '../error/error'
-import { callMonitored } from '../../tools/monitor'
 import type { ExperimentalFeature } from '../../tools/experimentalFeatures'
 import { addExperimentalFeatures } from '../../tools/experimentalFeatures'
 import { type Configuration } from '../configuration'

@@ -11,14 +11,14 @@ import {
   INTAKE_SITE_US1_FED,
   INTAKE_SITE_US2_FED,
 } from '@datadog/js-core/transport'
+import { startMonitorErrorCollection } from '@datadog/js-core/monitor'
 import type { Context } from '../../tools/serialisation/context'
 import { NO_ERROR_STACK_PRESENT_MESSAGE, isError } from '../error/isError'
 import { toStackTraceString } from '../../tools/stackTrace/handlingStack'
 import { getExperimentalFeatures } from '../../tools/experimentalFeatures'
 import type { Configuration } from '../configuration'
 import { buildTags } from '../tags'
 import { BufferedObservable, Observable } from '../../tools/observable'
-import { startMonitorErrorCollection } from '../../tools/monitor'
 import { display } from '../../tools/display'
 import { sendToExtension } from '../../tools/sendToExtension'
 import { jsonStringify } from '../../tools/serialisation/jsonStringify'

@@ -44,7 +44,6 @@ export {
   addTelemetryUsage,
   addTelemetryMetrics,
 } from './domain/telemetry'
-export { monitored, monitor, callMonitored, monitorError } from './tools/monitor'
 export type { Subscription } from './tools/observable'
 export { Observable, BufferedObservable } from './tools/observable'
 export type { SessionManager, SessionContext } from './domain/session/sessionManager'
@@ -72,7 +71,6 @@ export {
   bridgeSupports,
   BridgeCapability,
   createBatch,
-  createFlushController,
   FLUSH_DURATION_LIMIT,
 } from './transport'
 export * from './tools/display'

@@ -1,103 +1,2 @@
-import type { Uint8ArrayBuffer } from './utils/byteUtils'
-import { computeBytesCount } from './utils/byteUtils'
-
-export interface Encoder<Output extends string | Uint8ArrayBuffer = string | Uint8ArrayBuffer> {
-  /**
-   * Whether this encoder might call the provided callbacks asynchronously
-   */
-  isAsync: boolean
-
-  /**
-   * Whether some data has been written since the last finish() or finishSync() call
-   */
-  isEmpty: boolean
-
-  /**
-   * Write a string to be encoded.
-   *
-   * This operation can be synchronous or asynchronous depending on the encoder implementation.
-   *
-   * If specified, the callback will be invoked when the operation finishes, unless the operation is
-   * asynchronous and finish() or finishSync() is called in the meantime.
-   */
-  write(data: string, callback?: (additionalEncodedBytesCount: number) => void): void
-
-  /**
-   * Waits for pending data to be encoded and resets the encoder state.
-   *
-   * This operation can be synchronous or asynchronous depending on the encoder implementation.
-   *
-   * The callback will be invoked when the operation finishes, unless the operation is asynchronous
-   * and another call to finish() or finishSync() occurs in the meantime.
-   */
-  finish(callback: (result: EncoderResult<Output>) => void): void
-
-  /**
-   * Resets the encoder state then returns the encoded data and any potential pending data directly,
-   * discarding all pending write operations and finish() callbacks.
-   */
-  finishSync(): EncoderResult<Output> & { pendingData: string }
-
-  /**
-   * Returns a rough estimation of the bytes count if the data was encoded.
-   */
-  estimateEncodedBytesCount(data: string): number
-}
-
-export interface EncoderResult<Output extends string | Uint8ArrayBuffer = string | Uint8ArrayBuffer> {
-  output: Output
-  outputBytesCount: number
-
-  /**
-   * An encoding type supported by HTTP Content-Encoding, if applicable.
-   * See https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Encoding#directives
-   */
-  encoding?: 'deflate'
-
-  /**
-   * Total bytes count of the input strings encoded to UTF-8.
-   */
-  rawBytesCount: number
-}
-
-export function createIdentityEncoder(): Encoder<string> {
-  let output = ''
-  let outputBytesCount = 0
-
-  return {
-    isAsync: false,
-
-    get isEmpty() {
-      return !output
-    },
-
-    write(data, callback) {
-      const additionalEncodedBytesCount = computeBytesCount(data)
-      outputBytesCount += additionalEncodedBytesCount
-      output += data
-      if (callback) {
-        callback(additionalEncodedBytesCount)
-      }
-    },
-
-    finish(callback) {
-      callback(this.finishSync())
-    },
-
-    finishSync() {
-      const result = {
-        output,
-        outputBytesCount,
-        rawBytesCount: outputBytesCount,
-        pendingData: '',
-      }
-      output = ''
-      outputBytesCount = 0
-      return result
-    },
-
-    estimateEncodedBytesCount(data) {
-      return data.length
-    },
-  }
-}
+export type { Encoder, EncoderResult } from '@datadog/js-core/transport'
+export { createIdentityEncoder } from '@datadog/js-core/transport'
@@ -1,38 +1,2 @@
-import { globalObject } from '@datadog/js-core/util'
-
-export interface BrowserWindowWithZoneJs {
-  Zone?: {
-    // All Zone.js versions expose the __symbol__ method, but we observed that some website have a
-    // 'Zone' global variable unrelated to Zone.js, so let's consider this method optional
-    // nonetheless.
-    __symbol__?: (name: string) => string
-  }
-}
-
-/**
- * Gets the original value for a DOM API that was potentially patched by Zone.js.
- *
- * Zone.js[1] is a library that patches a bunch of JS and DOM APIs. It usually stores the original
- * value of the patched functions/constructors/methods in a hidden property prefixed by
- * __zone_symbol__.
- *
- * In multiple occasions, we observed that Zone.js is the culprit of important issues leading to
- * browser resource exhaustion (memory leak, high CPU usage). This method is used as a workaround to
- * use the original DOM API instead of the one patched by Zone.js.
- *
- * [1]: https://github.com/angular/angular/tree/main/packages/zone.js
- */
-export function getZoneJsOriginalValue<Target, Name extends keyof Target & string>(
-  target: Target,
-  name: Name
-): Target[Name] {
-  const browserWindow = globalObject as BrowserWindowWithZoneJs
-  let original: Target[Name] | undefined
-  if (browserWindow.Zone && typeof browserWindow.Zone.__symbol__ === 'function') {
-    original = (target as any)[browserWindow.Zone.__symbol__(name)]
-  }
-  if (!original) {
-    original = target[name]
-  }
-  return original
-}
+export type { BrowserWindowWithZoneJs } from '@datadog/js-core/util'
+export { getZoneJsOriginalValue } from '@datadog/js-core/util'
@@ -1,5 +1,5 @@
+import { callMonitored } from '@datadog/js-core/monitor'
 import { setTimeout } from './timer'
-import { callMonitored } from './monitor'
 import { noop } from './utils/functionUtils'
 import { createHandlingStack } from './stackTrace/handlingStack'
 

@@ -1,32 +1 @@
-declare const __BUILD_ENV__SDK_VERSION__: string
-
-export const mockableReplacements = new Map<unknown, unknown>()
-
-/**
- * Wraps a value to make it mockable in tests. In production builds, this is a no-op
- * that returns the value as-is. In test builds, it checks if a mock replacement has
- * been registered and returns that instead.
- *
- * @example
- * // In source file:
- * import { mockable } from '../tools/mockable'
- * export function formatNavigationEntry(): string {
- *   const navigationEntry = mockable(getNavigationEntry)()
- *   ...
- * }
- *
- * // In test file:
- * import { replaceMockable } from '@datadog/browser-core/test'
- * it('...', () => {
- *   replaceMockable(getNavigationEntry, () => FAKE_NAVIGATION_ENTRY)
- *   expect(formatNavigationEntry()).toEqual(...)
- * })
- */
-export function mockable<T>(value: T): T {
-  // In test builds, return a wrapper that checks for mocks at call time
-  if (__BUILD_ENV__SDK_VERSION__ === 'test' && mockableReplacements.has(value)) {
-    return mockableReplacements.get(value)! as T
-  }
-  // In production, return the value as-is
-  return value
-}
+export { mockable, mockableReplacements } from '@datadog/js-core/util'