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    use crate::io::AsyncWrite;

    use bytes::BufMut;
    use pin_project_lite::pin_project;
    use std::future::Future;
    use std::io;
    use std::marker::PhantomPinned;
    use std::mem::size_of;
    use std::pin::Pin;
    use std::task::{Context, Poll};

    macro_rules! writer {
        ($name:ident, $ty:ty, $writer:ident) => {
            writer!($name, $ty, $writer, size_of::<$ty>());
        };
        ($name:ident, $ty:ty, $writer:ident, $bytes:expr) => {
            pin_project! {
                #[doc(hidden)]
                #[must_use = "futures do nothing unless you `.await` or poll them"]
                pub struct $name<W> {
                    #[pin]
                    dst: W,
                    buf: [u8; $bytes],
                    written: u8,
                    // Make this future `!Unpin` for compatibility with async trait methods.
                    #[pin]
                    _pin: PhantomPinned,
                }
            }

            impl<W> $name<W> {
                pub(crate) fn new(w: W, value: $ty) -> Self {
                    let mut writer = Self {
                        buf: [0; $bytes],
                        written: 0,
                        dst: w,
                        _pin: PhantomPinned,
                    };
                    BufMut::$writer(&mut &mut writer.buf[..], value);
                    writer
                }
            }

            impl<W> Future for $name<W>
            where
                W: AsyncWrite,
            {
                type Output = io::Result<()>;

                fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
                    let mut me = self.project();

                    if *me.written == $bytes as u8 {
                        return Poll::Ready(Ok(()));
                    }

                    while *me.written < $bytes as u8 {
                        *me.written += match me
                            .dst
                            .as_mut()
                            .poll_write(cx, &me.buf[*me.written as usize..])
                        {
                            Poll::Pending => return Poll::Pending,
                            Poll::Ready(Err(e)) => return Poll::Ready(Err(e.into())),
                            Poll::Ready(Ok(0)) => {
                                return Poll::Ready(Err(io::ErrorKind::WriteZero.into()));
                            }
                            Poll::Ready(Ok(n)) => n as u8,
                        };
                    }
                    Poll::Ready(Ok(()))
                }
            }
        };
    }

    macro_rules! writer8 {
        ($name:ident, $ty:ty) => {
            pin_project! {
                #[doc(hidden)]
                #[must_use = "futures do nothing unless you `.await` or poll them"]
                pub struct $name<W> {
                    #[pin]
                    dst: W,
                    byte: $ty,
                    // Make this future `!Unpin` for compatibility with async trait methods.
                    #[pin]
                    _pin: PhantomPinned,
                }
            }

            impl<W> $name<W> {
                pub(crate) fn new(dst: W, byte: $ty) -> Self {
                    Self {
                        dst,
                        byte,
                        _pin: PhantomPinned,
                    }
                }
            }

            impl<W> Future for $name<W>
            where
                W: AsyncWrite,
            {
                type Output = io::Result<()>;

                fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
                    let me = self.project();

                    let buf = [*me.byte as u8];

                    match me.dst.poll_write(cx, &buf[..]) {
                        Poll::Pending => Poll::Pending,
                        Poll::Ready(Err(e)) => Poll::Ready(Err(e.into())),
                        Poll::Ready(Ok(0)) => Poll::Ready(Err(io::ErrorKind::WriteZero.into())),
                        Poll::Ready(Ok(1)) => Poll::Ready(Ok(())),
                        Poll::Ready(Ok(_)) => unreachable!(),
                    }
                }
            }
        };
    }

    writer8!(WriteU8, u8);
    writer8!(WriteI8, i8);

    writer!(WriteU16, u16, put_u16);
    writer!(WriteU32, u32, put_u32);
    writer!(WriteU64, u64, put_u64);
    writer!(WriteU128, u128, put_u128);

    writer!(WriteI16, i16, put_i16);
    writer!(WriteI32, i32, put_i32);
    writer!(WriteI64, i64, put_i64);
    writer!(WriteI128, i128, put_i128);

    writer!(WriteU16Le, u16, put_u16_le);
    writer!(WriteU32Le, u32, put_u32_le);
    writer!(WriteU64Le, u64, put_u64_le);
    writer!(WriteU128Le, u128, put_u128_le);

    writer!(WriteI16Le, i16, put_i16_le);
    writer!(WriteI32Le, i32, put_i32_le);
    writer!(WriteI64Le, i64, put_i64_le);
    writer!(WriteI128Le, i128, put_i128_le);