# inboundStreams(prepending:_:) Handle inbound streams and provide a closure on which callback handlers will be executed. When the `NetworkConnection` state moves to `ready`, the internal listener is registered with the system and can receive incoming streams on the multiplexing instance. `inboundStreams` should only be called once on a `NetworkConnection`, and multiple calls to run will throw an exception. ``` final func inboundStreams(@ProtocolStackBuilder prepending: @escaping (QUICStream) -> NewApplicationProtocol, _ handler: @escaping @isolated(any) @Sendable (QUIC.Stream) async throws -> Void) async throws where NewApplicationProtocol : OneToOneProtocol ``` ## Discussion If the `NetworkConnection` is not started at the time that `inboundStreams` is invoked, it will be started. The passed protocols in the `prepending` ProtocolStackBuilder will be added on top of the inbound streams. The closure inherits the isolation domain of the caller. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)