diff --git a/FirebaseCombineSwift/Tests/Unit/FirebaseCombine-unit-Bridging-Header.h b/FirebaseCombineSwift/Tests/Unit/FirebaseCombine-unit-Bridging-Header.h
index d61e7a7535d0..513e02610ade 100644
--- a/FirebaseCombineSwift/Tests/Unit/FirebaseCombine-unit-Bridging-Header.h
+++ b/FirebaseCombineSwift/Tests/Unit/FirebaseCombine-unit-Bridging-Header.h
@@ -16,4 +16,4 @@
 #import "SharedTestUtilities/FIROptionsMock.h"
 
 // Firebase Core
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
diff --git a/FirebaseCore/CMakeLists.txt b/FirebaseCore/CMakeLists.txt
index 5117556d606b..10de26fc5b13 100644
--- a/FirebaseCore/CMakeLists.txt
+++ b/FirebaseCore/CMakeLists.txt
@@ -19,8 +19,8 @@ endif()
 # GoogleUtilities is an external dependency without its own cmake configuration.
 include(GoogleUtilities)
 
-file(GLOB headers Sources/Private/*.h Sources/Public/FirebaseCore/*.h)
-file(GLOB sources Sources/*.m)
+file(GLOB headers Sources/Private/*.h Sources/Public/FirebaseCore/*.h Sources/InternalObjC/*.h)
+file(GLOB sources Sources/*.m Sources/InternalObjC/*.m)
 
 podspec_version(version ${PROJECT_SOURCE_DIR}/FirebaseCore.podspec)
 firebase_version(firebase_version ${PROJECT_SOURCE_DIR}/FirebaseCore.podspec)
diff --git a/FirebaseCore/Extension/FirebaseCoreInternal.h b/FirebaseCore/Extension/FirebaseCoreExtension.h
similarity index 100%
rename from FirebaseCore/Extension/FirebaseCoreInternal.h
rename to FirebaseCore/Extension/FirebaseCoreExtension.h
diff --git a/FirebaseCore/Sources/FIROptions.m b/FirebaseCore/Sources/FIROptions.m
index 976a0da77926..7ec49d4ddb20 100644
--- a/FirebaseCore/Sources/FIROptions.m
+++ b/FirebaseCore/Sources/FIROptions.m
@@ -13,7 +13,8 @@
 // limitations under the License.
 
 #import "FirebaseCore/Extension/FIRAppInternal.h"
-@import FirebaseCoreInternal;
+
+#import "FirebaseCore/InternalObjC/FirebaseCoreInternal.h"
 #if SWIFT_PACKAGE
 @import FirebaseCoreInternalObjC;
 #endif
diff --git a/FirebaseCore/Tests/SwiftUnit/FirebaseCore-unit-Bridging-Header.h b/FirebaseCore/Tests/SwiftUnit/FirebaseCore-unit-Bridging-Header.h
index 93325036a025..18f7243cefda 100644
--- a/FirebaseCore/Tests/SwiftUnit/FirebaseCore-unit-Bridging-Header.h
+++ b/FirebaseCore/Tests/SwiftUnit/FirebaseCore-unit-Bridging-Header.h
@@ -12,6 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "SharedTestUtilities/ExceptionCatcher.h"
 #import "SharedTestUtilities/FIROptionsMock.h"
diff --git a/FirebaseFunctions/Tests/ObjCIntegration/FIRIntegrationTests.m b/FirebaseFunctions/Tests/ObjCIntegration/FIRIntegrationTests.m
index 124f2eb90440..7c3d1a090b10 100644
--- a/FirebaseFunctions/Tests/ObjCIntegration/FIRIntegrationTests.m
+++ b/FirebaseFunctions/Tests/ObjCIntegration/FIRIntegrationTests.m
@@ -14,7 +14,7 @@
 
 #import <XCTest/XCTest.h>
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseFunctions/Tests/ObjCIntegration/FIRFunctions+Internal.h"
 
 @import FirebaseFunctions;
diff --git a/FirebaseInAppMessaging/Sources/DefaultUI/FIRCore+InAppMessagingDisplay.h b/FirebaseInAppMessaging/Sources/DefaultUI/FIRCore+InAppMessagingDisplay.h
index 91b15a75afb4..185288bc4ad0 100644
--- a/FirebaseInAppMessaging/Sources/DefaultUI/FIRCore+InAppMessagingDisplay.h
+++ b/FirebaseInAppMessaging/Sources/DefaultUI/FIRCore+InAppMessagingDisplay.h
@@ -14,8 +14,6 @@
  * limitations under the License.
  */
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
-
 // This file contains declarations that should go into FirebaseCore when
 // Firebase InAppMessagingDisplay is merged into main. Keep them separate now to help
 // with build from development folder and avoid merge conflicts.
diff --git a/FirebaseInAppMessaging/Sources/FIRInAppMessaging.m b/FirebaseInAppMessaging/Sources/FIRInAppMessaging.m
index a30e2d0eb119..445e2daca1e1 100644
--- a/FirebaseInAppMessaging/Sources/FIRInAppMessaging.m
+++ b/FirebaseInAppMessaging/Sources/FIRInAppMessaging.m
@@ -21,7 +21,6 @@
 
 #import <Foundation/Foundation.h>
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
 #import "FirebaseInstallations/Source/Library/Private/FirebaseInstallationsInternal.h"
 #import "Interop/Analytics/Public/FIRAnalyticsInterop.h"
 
diff --git a/FirebaseInAppMessaging/Sources/Flows/FIRIAMDisplayCheckOnAnalyticEventsFlow.m b/FirebaseInAppMessaging/Sources/Flows/FIRIAMDisplayCheckOnAnalyticEventsFlow.m
index 4e3a1491919d..56b110886da2 100644
--- a/FirebaseInAppMessaging/Sources/Flows/FIRIAMDisplayCheckOnAnalyticEventsFlow.m
+++ b/FirebaseInAppMessaging/Sources/Flows/FIRIAMDisplayCheckOnAnalyticEventsFlow.m
@@ -17,7 +17,6 @@
 #import <TargetConditionals.h>
 #if TARGET_OS_IOS || TARGET_OS_TV || TARGET_OS_VISION
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
 #import "Interop/Analytics/Public/FIRAnalyticsInterop.h"
 #import "Interop/Analytics/Public/FIRAnalyticsInteropListener.h"
 
diff --git a/FirebaseMessaging/Sources/FIRMessagingUtilities.m b/FirebaseMessaging/Sources/FIRMessagingUtilities.m
index 70939e702350..6072a15d9478 100644
--- a/FirebaseMessaging/Sources/FIRMessagingUtilities.m
+++ b/FirebaseMessaging/Sources/FIRMessagingUtilities.m
@@ -18,7 +18,7 @@
 
 #import <GoogleUtilities/GULAppEnvironmentUtil.h>
 #import <GoogleUtilities/GULUserDefaults.h>
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseMessaging/Sources/FIRMessagingLogger.h"
 
 NSString *const kFIRMessagingInstanceIDUserDefaultsKeyLocale =
diff --git a/FirebaseMessaging/Sources/Token/FIRMessagingTokenFetchOperation.m b/FirebaseMessaging/Sources/Token/FIRMessagingTokenFetchOperation.m
index ffb3fdb736cc..0062241eb9b8 100644
--- a/FirebaseMessaging/Sources/Token/FIRMessagingTokenFetchOperation.m
+++ b/FirebaseMessaging/Sources/Token/FIRMessagingTokenFetchOperation.m
@@ -25,7 +25,7 @@
 #import "FirebaseMessaging/Sources/Token/FIRMessagingCheckinPreferences.h"
 #import "FirebaseMessaging/Sources/Token/FIRMessagingTokenOperation.h"
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 
 // We can have a static int since this error should theoretically only
 // happen once (for the first time). If it repeats there is something
diff --git a/FirebaseMessaging/Tests/UnitTests/FIRMessagingHandlingTest.m b/FirebaseMessaging/Tests/UnitTests/FIRMessagingHandlingTest.m
index 92509ec26a77..90e770dd7691 100644
--- a/FirebaseMessaging/Tests/UnitTests/FIRMessagingHandlingTest.m
+++ b/FirebaseMessaging/Tests/UnitTests/FIRMessagingHandlingTest.m
@@ -19,7 +19,7 @@
 #import <OCMock/OCMock.h>
 
 #import <GoogleUtilities/GULUserDefaults.h>
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseMessaging/Sources/Public/FirebaseMessaging/FIRMessaging.h"
 #import "Interop/Analytics/Public/FIRAnalyticsInterop.h"
 
diff --git a/FirebaseMessaging/Tests/UnitTests/FIRMessagingTest.m b/FirebaseMessaging/Tests/UnitTests/FIRMessagingTest.m
index 8ef1952552e7..227b94350e71 100644
--- a/FirebaseMessaging/Tests/UnitTests/FIRMessagingTest.m
+++ b/FirebaseMessaging/Tests/UnitTests/FIRMessagingTest.m
@@ -18,7 +18,7 @@
 #import <XCTest/XCTest.h>
 
 #import <GoogleUtilities/GULUserDefaults.h>
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseMessaging/Sources/FIRMessaging_Private.h"
 #import "FirebaseMessaging/Sources/Public/FirebaseMessaging/FIRMessaging.h"
 #import "FirebaseMessaging/Sources/Token/FIRMessagingTokenManager.h"
diff --git a/FirebaseMessaging/Tests/UnitTests/FIRMessagingTestUtilities.m b/FirebaseMessaging/Tests/UnitTests/FIRMessagingTestUtilities.m
index c653d111fc16..034fb72760a1 100644
--- a/FirebaseMessaging/Tests/UnitTests/FIRMessagingTestUtilities.m
+++ b/FirebaseMessaging/Tests/UnitTests/FIRMessagingTestUtilities.m
@@ -17,7 +17,7 @@
 #import <OCMock/OCMock.h>
 
 #import <GoogleUtilities/GULUserDefaults.h>
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseInstallations/Source/Library/Private/FirebaseInstallationsInternal.h"
 #import "FirebaseMessaging/Sources/FIRMessagingPubSub.h"
 #import "FirebaseMessaging/Sources/FIRMessagingRmqManager.h"
diff --git a/FirebaseMessaging/Tests/UnitTests/FIRMessagingTokenInfoTest.m b/FirebaseMessaging/Tests/UnitTests/FIRMessagingTokenInfoTest.m
index 13d353b1d02e..20b586125154 100644
--- a/FirebaseMessaging/Tests/UnitTests/FIRMessagingTokenInfoTest.m
+++ b/FirebaseMessaging/Tests/UnitTests/FIRMessagingTokenInfoTest.m
@@ -19,7 +19,7 @@
 #import <XCTest/XCTest.h>
 
 #import <OCMock/OCMock.h>
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseMessaging/Sources/FIRMessagingUtilities.h"
 #import "FirebaseMessaging/Sources/Token/FIRMessagingAPNSInfo.h"
 
diff --git a/FirebaseMessaging/Tests/UnitTests/FIRMessagingTokenOperationsTest.m b/FirebaseMessaging/Tests/UnitTests/FIRMessagingTokenOperationsTest.m
index 0459a8d3e385..431fe5c506b8 100644
--- a/FirebaseMessaging/Tests/UnitTests/FIRMessagingTokenOperationsTest.m
+++ b/FirebaseMessaging/Tests/UnitTests/FIRMessagingTokenOperationsTest.m
@@ -18,7 +18,7 @@
 
 #import <OCMock/OCMock.h>
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseInstallations/Source/Library/Private/FirebaseInstallationsInternal.h"
 #import "FirebaseMessaging/Sources/FIRMessagingConstants.h"
 #import "FirebaseMessaging/Sources/NSError+FIRMessaging.h"
diff --git a/FirebasePerformance/Sources/Configurations/FPRConfigurations.m b/FirebasePerformance/Sources/Configurations/FPRConfigurations.m
index 9d498a570234..6b4941a3c686 100644
--- a/FirebasePerformance/Sources/Configurations/FPRConfigurations.m
+++ b/FirebasePerformance/Sources/Configurations/FPRConfigurations.m
@@ -23,7 +23,7 @@
 #import "FirebasePerformance/Sources/Configurations/FPRRemoteConfigFlags+Private.h"
 #import "FirebasePerformance/Sources/Configurations/FPRRemoteConfigFlags.h"
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 
 FPRConfigName kFPRConfigDataCollectionEnabled = @"dataCollectionEnabled";
 
diff --git a/FirebasePerformance/Tests/Unit/Fakes/FIRAppFake.m b/FirebasePerformance/Tests/Unit/Fakes/FIRAppFake.m
index 11446ffac904..1173806f08a9 100644
--- a/FirebasePerformance/Tests/Unit/Fakes/FIRAppFake.m
+++ b/FirebasePerformance/Tests/Unit/Fakes/FIRAppFake.m
@@ -14,7 +14,7 @@
 
 #import "FirebasePerformance/Tests/Unit/Fakes/FIRAppFake.h"
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 
 @implementation FIRAppFake
 
diff --git a/FirebaseRemoteConfig/Sources/RCNDevice.m b/FirebaseRemoteConfig/Sources/RCNDevice.m
index 3819ff26fbd6..69cdc79f4ba1 100644
--- a/FirebaseRemoteConfig/Sources/RCNDevice.m
+++ b/FirebaseRemoteConfig/Sources/RCNDevice.m
@@ -19,7 +19,7 @@
 #import <sys/utsname.h>
 
 #import <GoogleUtilities/GULAppEnvironmentUtil.h>
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseRemoteConfig/Sources/Private/RCNConfigSettings.h"
 #import "FirebaseRemoteConfig/Sources/RCNConfigConstants.h"
 
diff --git a/FirebaseRemoteConfig/Sources/RCNUserDefaultsManager.m b/FirebaseRemoteConfig/Sources/RCNUserDefaultsManager.m
index 85b3124c9aec..7ee69c165db5 100644
--- a/FirebaseRemoteConfig/Sources/RCNUserDefaultsManager.m
+++ b/FirebaseRemoteConfig/Sources/RCNUserDefaultsManager.m
@@ -15,7 +15,7 @@
  */
 
 #import "FirebaseRemoteConfig/Sources/RCNUserDefaultsManager.h"
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseRemoteConfig/Sources/Public/FirebaseRemoteConfig/FIRRemoteConfig.h"
 #import "FirebaseRemoteConfig/Sources/RCNConfigConstants.h"
 
diff --git a/FirebaseRemoteConfig/Tests/Unit/RCNConfigDBManagerTest.m b/FirebaseRemoteConfig/Tests/Unit/RCNConfigDBManagerTest.m
index 773af690935f..09a2244ff595 100644
--- a/FirebaseRemoteConfig/Tests/Unit/RCNConfigDBManagerTest.m
+++ b/FirebaseRemoteConfig/Tests/Unit/RCNConfigDBManagerTest.m
@@ -19,7 +19,7 @@
 
 #import <sqlite3.h>
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseRemoteConfig/Sources/Private/RCNConfigSettings.h"
 #import "FirebaseRemoteConfig/Sources/RCNConfigConstants.h"
 #import "FirebaseRemoteConfig/Sources/RCNConfigContent.h"
diff --git a/FirebaseRemoteConfig/Tests/Unit/RCNPersonalizationTest.m b/FirebaseRemoteConfig/Tests/Unit/RCNPersonalizationTest.m
index bdd8ab0b8bcd..bf8ab69ea7b2 100644
--- a/FirebaseRemoteConfig/Tests/Unit/RCNPersonalizationTest.m
+++ b/FirebaseRemoteConfig/Tests/Unit/RCNPersonalizationTest.m
@@ -17,7 +17,7 @@
 #import <OCMock/OCMock.h>
 #import <XCTest/XCTest.h>
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseRemoteConfig/Sources/Private/FIRRemoteConfig_Private.h"
 #import "FirebaseRemoteConfig/Sources/Private/RCNConfigFetch.h"
 #import "FirebaseRemoteConfig/Sources/RCNConfigConstants.h"
diff --git a/FirebaseRemoteConfig/Tests/Unit/RCNRemoteConfig+FIRAppTest.m b/FirebaseRemoteConfig/Tests/Unit/RCNRemoteConfig+FIRAppTest.m
index 00704690521a..78d3c02413e0 100644
--- a/FirebaseRemoteConfig/Tests/Unit/RCNRemoteConfig+FIRAppTest.m
+++ b/FirebaseRemoteConfig/Tests/Unit/RCNRemoteConfig+FIRAppTest.m
@@ -18,7 +18,7 @@
 #import <XCTest/XCTest.h>
 
 // #import "FIRRemoteConfig+FIRApp.h"
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 #import "FirebaseRemoteConfig/Sources/Private/FIRRemoteConfig_Private.h"
 // #import "third_party/firebase/ios/Releases/FirebaseCore/Tests/FIRTestCase.h"
 
diff --git a/FirebaseRemoteConfig/Tests/Unit/RCNRemoteConfigTest.m b/FirebaseRemoteConfig/Tests/Unit/RCNRemoteConfigTest.m
index e84bd024b8b4..a197b21d4df2 100644
--- a/FirebaseRemoteConfig/Tests/Unit/RCNRemoteConfigTest.m
+++ b/FirebaseRemoteConfig/Tests/Unit/RCNRemoteConfigTest.m
@@ -31,7 +31,7 @@
 #import "FirebaseRemoteConfig/Tests/Unit/RCNTestUtilities.h"
 
 #import <GoogleUtilities/GULNSData+zlib.h>
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 @import FirebaseRemoteConfigInterop;
 
 @protocol FIRRolloutsStateSubscriber;
diff --git a/FirebaseRemoteConfig/Tests/Unit/RCNThrottlingTests.m b/FirebaseRemoteConfig/Tests/Unit/RCNThrottlingTests.m
index 5429c61df1f3..b1cf83f20345 100644
--- a/FirebaseRemoteConfig/Tests/Unit/RCNThrottlingTests.m
+++ b/FirebaseRemoteConfig/Tests/Unit/RCNThrottlingTests.m
@@ -24,7 +24,7 @@
 #import "FirebaseRemoteConfig/Sources/RCNConfigExperiment.h"
 #import "FirebaseRemoteConfig/Tests/Unit/RCNTestUtilities.h"
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 @import FirebaseRemoteConfigInterop;
 
 @interface RCNThrottlingTests : XCTestCase {
diff --git a/FirebaseStorage/Tests/ObjCIntegration/FIRStorageIntegrationTests.m b/FirebaseStorage/Tests/ObjCIntegration/FIRStorageIntegrationTests.m
index bad1bdfa8218..113ed884838b 100644
--- a/FirebaseStorage/Tests/ObjCIntegration/FIRStorageIntegrationTests.m
+++ b/FirebaseStorage/Tests/ObjCIntegration/FIRStorageIntegrationTests.m
@@ -17,7 +17,7 @@
 @import FirebaseAuth;
 @import FirebaseStorage;
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 
 #import "FirebaseStorage/Tests/ObjCIntegration/Credentials.h"
 
diff --git a/HeadersImports.md b/HeadersImports.md
index 847c1748afe1..d7bf70a1545a 100644
--- a/HeadersImports.md
+++ b/HeadersImports.md
@@ -47,7 +47,7 @@ In Swift Package Manager, it's a library target.
   import like `#import "publicHeader.h"` to avoid public module collisions.
 
 * *Private Headers from other Libraries* - Import a private umbrella header like
-  `FirebaseCore/Extension/FIRebaseCoreInternal.h`. For CocoaPods, these files should be
+  `FirebaseCore/Extension/FirebaseCoreExtension.h`. For CocoaPods, these files should be
   added to the podspec in the `source_files` attribute like:
 ```
   s.source_files = [ 'FirebaseFoo/Sources/**/*.[mh]'
diff --git a/Interop/FirebaseComponentSystem.md b/Interop/FirebaseComponentSystem.md
index ab881ff54028..ef0ceca2b7ae 100644
--- a/Interop/FirebaseComponentSystem.md
+++ b/Interop/FirebaseComponentSystem.md
@@ -87,7 +87,7 @@ Each Firebase framework should register with Core in the `+load` method of the c
 dependencies before a class has a chance to be called by a developer (if called at all).
 
 ```obj-c
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 
 @interface FIRFoo <FIRLibrary>
 @end
diff --git a/SharedTestUtilities/FIRSampleAppUtilities.m b/SharedTestUtilities/FIRSampleAppUtilities.m
index 8f088b934207..dae295b23a98 100644
--- a/SharedTestUtilities/FIRSampleAppUtilities.m
+++ b/SharedTestUtilities/FIRSampleAppUtilities.m
@@ -22,7 +22,7 @@
 #import <SafariServices/SafariServices.h>
 #endif
 
-#import "FirebaseCore/Extension/FirebaseCoreInternal.h"
+#import "FirebaseCore/Extension/FirebaseCoreExtension.h"
 
 NSString *const kGoogleAppIDPlistKey = @"GOOGLE_APP_ID";
 // Dummy plist GOOGLE_APP_ID