diff --git a/Sources/FirebaseCore/FutureProtocol.swift b/Sources/FirebaseCore/FutureProtocol.swift
index c5c31e6..342b551 100644
--- a/Sources/FirebaseCore/FutureProtocol.swift
+++ b/Sources/FirebaseCore/FutureProtocol.swift
@@ -20,7 +20,7 @@ public protocol FutureProtocol {
   func error() -> Int32
   func __error_messageUnsafe() -> UnsafePointer<CChar>?
   func __resultUnsafe() -> UnsafePointer<ResultType>?
-  func CallOnCompletion(
+  func OnCompletion(
     _ completion: FutureCompletionType,
     _ user_data: UnsafeMutableRawPointer?
   )
@@ -35,7 +35,7 @@ public extension FutureProtocol {
   // While the underlying Firebase `OnCompletion` method can provide a reference
   // back to the Future, we don't need to expose that here.
   func setCompletion(_ completion: @escaping () -> Void) {
-    CallOnCompletion({ ptr in
+    OnCompletion({ ptr in
       Unmanaged<CompletionReference>.fromOpaque(ptr!).takeRetainedValue().completion()
     }, Unmanaged.passRetained(CompletionReference(completion)).toOpaque())
   }
diff --git a/Sources/firebase/include/FirebaseCore.hh b/Sources/firebase/include/FirebaseCore.hh
index f1ee6fc..a34956c 100644
--- a/Sources/firebase/include/FirebaseCore.hh
+++ b/Sources/firebase/include/FirebaseCore.hh
@@ -20,12 +20,13 @@ template <class R> class ConformingFuture: public ::firebase::Future<R> {
 
   ConformingFuture(const FutureType& rhs) : FutureType(rhs) {}
 
-  void CallOnCompletion(
+  void OnCompletion(
       _Nonnull FutureCompletionType completion,
       _Nullable void* user_data) const {
-    OnCompletion([completion, user_data](const FutureBase&) {
-      completion(user_data);
-    });
+    ::firebase::FutureBase::OnCompletion(
+        [completion, user_data](const FutureBase&) {
+          completion(user_data);
+        });
   }
 } __attribute__((swift_attr("conforms_to:FirebaseCore.FutureProtocol")));