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diff --git a/third_party/rust/tokio/src/task/builder.rs b/third_party/rust/tokio/src/task/builder.rs
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+++ b/third_party/rust/tokio/src/task/builder.rs
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+#![allow(unreachable_pub)]
+use crate::{runtime::context, task::JoinHandle};
+use std::future::Future;
+
+/// Factory which is used to configure the properties of a new task.
+///
+/// **Note**: This is an [unstable API][unstable]. The public API of this type
+/// may break in 1.x releases. See [the documentation on unstable
+/// features][unstable] for details.
+///
+/// Methods can be chained in order to configure it.
+///
+/// Currently, there is only one configuration option:
+///
+/// - [`name`], which specifies an associated name for
+///   the task
+///
+/// There are three types of task that can be spawned from a Builder:
+/// - [`spawn_local`] for executing futures on the current thread
+/// - [`spawn`] for executing [`Send`] futures on the runtime
+/// - [`spawn_blocking`] for executing blocking code in the
+///   blocking thread pool.
+///
+/// ## Example
+///
+/// ```no_run
+/// use tokio::net::{TcpListener, TcpStream};
+///
+/// use std::io;
+///
+/// async fn process(socket: TcpStream) {
+///     // ...
+/// # drop(socket);
+/// }
+///
+/// #[tokio::main]
+/// async fn main() -> io::Result<()> {
+///     let listener = TcpListener::bind("127.0.0.1:8080").await?;
+///
+///     loop {
+///         let (socket, _) = listener.accept().await?;
+///
+///         tokio::task::Builder::new()
+///             .name("tcp connection handler")
+///             .spawn(async move {
+///                 // Process each socket concurrently.
+///                 process(socket).await
+///             });
+///     }
+/// }
+/// ```
+/// [unstable]: crate#unstable-features
+/// [`name`]: Builder::name
+/// [`spawn_local`]: Builder::spawn_local
+/// [`spawn`]: Builder::spawn
+/// [`spawn_blocking`]: Builder::spawn_blocking
+#[derive(Default, Debug)]
+#[cfg_attr(docsrs, doc(cfg(all(tokio_unstable, feature = "tracing"))))]
+pub struct Builder<'a> {
+    name: Option<&'a str>,
+}
+
+impl<'a> Builder<'a> {
+    /// Creates a new task builder.
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Assigns a name to the task which will be spawned.
+    pub fn name(&self, name: &'a str) -> Self {
+        Self { name: Some(name) }
+    }
+
+    /// Spawns a task on the executor.
+    ///
+    /// See [`task::spawn`](crate::task::spawn) for
+    /// more details.
+    #[track_caller]
+    pub fn spawn<Fut>(self, future: Fut) -> JoinHandle<Fut::Output>
+    where
+        Fut: Future + Send + 'static,
+        Fut::Output: Send + 'static,
+    {
+        super::spawn::spawn_inner(future, self.name)
+    }
+
+    /// Spawns a task on the current thread.
+    ///
+    /// See [`task::spawn_local`](crate::task::spawn_local)
+    /// for more details.
+    #[track_caller]
+    pub fn spawn_local<Fut>(self, future: Fut) -> JoinHandle<Fut::Output>
+    where
+        Fut: Future + 'static,
+        Fut::Output: 'static,
+    {
+        super::local::spawn_local_inner(future, self.name)
+    }
+
+    /// Spawns blocking code on the blocking threadpool.
+    ///
+    /// See [`task::spawn_blocking`](crate::task::spawn_blocking)
+    /// for more details.
+    #[track_caller]
+    pub fn spawn_blocking<Function, Output>(self, function: Function) -> JoinHandle<Output>
+    where
+        Function: FnOnce() -> Output + Send + 'static,
+        Output: Send + 'static,
+    {
+        use crate::runtime::Mandatory;
+        let (join_handle, _was_spawned) =
+            context::current().spawn_blocking_inner(function, Mandatory::NonMandatory, self.name);
+        join_handle
+    }
+}