How to set server TCP socket options such as TCP_NODELAY?

[sanmai-NL]

hyper has an API for that, see https://docs.rs/hyper/0.12.7/hyper/server/struct.Builder.html#method.tcp_nodelay. However based on the server example code of hyper-rustls, I do not get the required hyper::server::Builder<Incoming>, but a complex type hyper::server::Builder<futures::stream::filter_map::FilterMap<futures::stream::then::Then<futures::stream::and_then::AndThen<tokio_tcp::incoming::Incoming, [closure@webserver/src/lib.rs:328:19: 328:51 serverconfig:_], tokio_rustls::AcceptAsync<tokio_tcp::stream::TcpStream>>, [closure@webserver/src/lib.rs:329:15: 337:10], std::result::Result<std::option::Option<tokio_rustls::TlsStream<tokio_tcp::stream::TcpStream, rustls::server::ServerSession>>, std::io::Error>>, [closure@webserver/src/lib.rs:338:21: 338:26]>>. How to proceed?