diff --git a/contrib/lib/src/databases.rs b/contrib/lib/src/databases.rs
index 64a9e3f5..1d8000d2 100644
--- a/contrib/lib/src/databases.rs
+++ b/contrib/lib/src/databases.rs
@@ -50,7 +50,7 @@
 //! In your application's source code, one-time:
 //!
 //! ```rust
-//! #![feature(proc_macro_hygiene)]
+//! #![feature(proc_macro_hygiene, async_await)]
 //!
 //! #[macro_use] extern crate rocket;
 //! #[macro_use] extern crate rocket_contrib;
diff --git a/contrib/lib/src/uuid.rs b/contrib/lib/src/uuid.rs
index 5fab5efd..dd86a7ff 100644
--- a/contrib/lib/src/uuid.rs
+++ b/contrib/lib/src/uuid.rs
@@ -42,7 +42,7 @@ pub use self::uuid_crate::parser::ParseError;
 /// You can use the `Uuid` type directly as a target of a dynamic parameter:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # #[macro_use] extern crate rocket_contrib;
 /// use rocket_contrib::uuid::Uuid;
@@ -56,7 +56,7 @@ pub use self::uuid_crate::parser::ParseError;
 /// You can also use the `Uuid` as a form value, including in query strings:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # #[macro_use] extern crate rocket_contrib;
 /// use rocket_contrib::uuid::Uuid;
diff --git a/contrib/lib/tests/compress_responder.rs b/contrib/lib/tests/compress_responder.rs
index 2d317ddf..fdef99c0 100644
--- a/contrib/lib/tests/compress_responder.rs
+++ b/contrib/lib/tests/compress_responder.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use]
 #[cfg(all(feature = "brotli_compression", feature = "gzip_compression"))]
diff --git a/contrib/lib/tests/compression_fairing.rs b/contrib/lib/tests/compression_fairing.rs
index fa09188d..491957a9 100644
--- a/contrib/lib/tests/compression_fairing.rs
+++ b/contrib/lib/tests/compression_fairing.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use]
 #[cfg(all(feature = "brotli_compression", feature = "gzip_compression"))]
diff --git a/core/codegen/src/lib.rs b/core/codegen/src/lib.rs
index db72073b..7287cc8c 100644
--- a/core/codegen/src/lib.rs
+++ b/core/codegen/src/lib.rs
@@ -30,7 +30,7 @@
 //! crate root:
 //!
 //! ```rust
-//! #![feature(proc_macro_hygiene)]
+//! #![feature(proc_macro_hygiene, async_await)]
 //!
 //! #[macro_use] extern crate rocket;
 //! # #[get("/")] fn hello() { }
@@ -40,7 +40,7 @@
 //! Or, alternatively, selectively import from the top-level scope:
 //!
 //! ```rust
-//! #![feature(proc_macro_hygiene)]
+//! #![feature(proc_macro_hygiene, async_await)]
 //! # extern crate rocket;
 //!
 //! use rocket::{get, routes};
@@ -147,7 +147,7 @@ macro_rules! route_attribute {
         /// functions:
         ///
         /// ```rust
-        /// # #![feature(proc_macro_hygiene)]
+        /// # #![feature(proc_macro_hygiene, async_await)]
         /// # #[macro_use] extern crate rocket;
         /// #
         /// #[get("/")]
@@ -170,7 +170,7 @@ macro_rules! route_attribute {
         /// explicitly specified:
         ///
         /// ```rust
-        /// # #![feature(proc_macro_hygiene)]
+        /// # #![feature(proc_macro_hygiene, async_await)]
         /// # #[macro_use] extern crate rocket;
         /// #
         /// #[route(GET, path = "/")]
@@ -231,7 +231,7 @@ macro_rules! route_attribute {
         /// the arguments `foo`, `baz`, `msg`, `rest`, and `form`:
         ///
         /// ```rust
-        /// # #![feature(proc_macro_hygiene)]
+        /// # #![feature(proc_macro_hygiene, async_await)]
         /// # #[macro_use] extern crate rocket;
         /// # use rocket::request::Form;
         /// # use std::path::PathBuf;
@@ -343,7 +343,7 @@ route_attribute!(options => Method::Options);
 /// This attribute can only be applied to free functions:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// use rocket::Request;
@@ -755,7 +755,7 @@ pub fn derive_uri_display_path(input: TokenStream) -> TokenStream {
 /// corresponding [`Route`] structures. For example, given the following routes:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// #[get("/")]
@@ -770,7 +770,7 @@ pub fn derive_uri_display_path(input: TokenStream) -> TokenStream {
 /// The `routes!` macro can be used as:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// # use rocket::http::Method;
@@ -814,7 +814,7 @@ pub fn routes(input: TokenStream) -> TokenStream {
 /// catchers:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// #[catch(404)]
@@ -829,7 +829,7 @@ pub fn routes(input: TokenStream) -> TokenStream {
 /// The `catchers!` macro can be used as:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// # #[catch(404)] fn not_found() { /* .. */ }
@@ -871,7 +871,7 @@ pub fn catchers(input: TokenStream) -> TokenStream {
 /// For example, for the following route:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// #[get("/person/<name>?<age>")]
@@ -885,7 +885,7 @@ pub fn catchers(input: TokenStream) -> TokenStream {
 /// A URI can be created as follows:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// # #[get("/person/<name>?<age>")]
diff --git a/core/codegen/tests/expansion.rs b/core/codegen/tests/expansion.rs
index aaaf2fcd..d5d4f00e 100644
--- a/core/codegen/tests/expansion.rs
+++ b/core/codegen/tests/expansion.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/responder.rs b/core/codegen/tests/responder.rs
index 0df09bc6..9608faf0 100644
--- a/core/codegen/tests/responder.rs
+++ b/core/codegen/tests/responder.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 use rocket::local::Client;
 use rocket::response::Responder;
diff --git a/core/codegen/tests/route-data.rs b/core/codegen/tests/route-data.rs
index e15f4bb5..8a9cbc6f 100644
--- a/core/codegen/tests/route-data.rs
+++ b/core/codegen/tests/route-data.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/route-format.rs b/core/codegen/tests/route-format.rs
index 32bb935c..d29e77cb 100644
--- a/core/codegen/tests/route-format.rs
+++ b/core/codegen/tests/route-format.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/route-ranking.rs b/core/codegen/tests/route-ranking.rs
index a85ee24c..5fcc364b 100644
--- a/core/codegen/tests/route-ranking.rs
+++ b/core/codegen/tests/route-ranking.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/typed-uris.rs b/core/codegen/tests/typed-uris.rs
index 7f366e7e..47d313bc 100644
--- a/core/codegen/tests/typed-uris.rs
+++ b/core/codegen/tests/typed-uris.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 #![allow(dead_code, unused_variables)]
 
 #[macro_use] extern crate rocket;
diff --git a/core/codegen/tests/ui-fail/catchers.rs b/core/codegen/tests/ui-fail/catchers.rs
index 627bf0c2..0168f3cd 100644
--- a/core/codegen/tests/ui-fail/catchers.rs
+++ b/core/codegen/tests/ui-fail/catchers.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/ui-fail/route-attribute-general-syntax.rs b/core/codegen/tests/ui-fail/route-attribute-general-syntax.rs
index 8457f96b..6f3dfda1 100644
--- a/core/codegen/tests/ui-fail/route-attribute-general-syntax.rs
+++ b/core/codegen/tests/ui-fail/route-attribute-general-syntax.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/ui-fail/route-path-bad-syntax.rs b/core/codegen/tests/ui-fail/route-path-bad-syntax.rs
index ab6a8a4a..1f79e386 100644
--- a/core/codegen/tests/ui-fail/route-path-bad-syntax.rs
+++ b/core/codegen/tests/ui-fail/route-path-bad-syntax.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/ui-fail/route-type-errors.rs b/core/codegen/tests/ui-fail/route-type-errors.rs
index f97645ae..6cedb32f 100644
--- a/core/codegen/tests/ui-fail/route-type-errors.rs
+++ b/core/codegen/tests/ui-fail/route-type-errors.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/ui-fail/route-warnings.rs b/core/codegen/tests/ui-fail/route-warnings.rs
index 9111a216..57e3c93d 100644
--- a/core/codegen/tests/ui-fail/route-warnings.rs
+++ b/core/codegen/tests/ui-fail/route-warnings.rs
@@ -1,6 +1,6 @@
 // must-compile-successfully
 
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/ui-fail/routes.rs b/core/codegen/tests/ui-fail/routes.rs
index 954293a5..75952d25 100644
--- a/core/codegen/tests/ui-fail/routes.rs
+++ b/core/codegen/tests/ui-fail/routes.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/ui-fail/typed-uri-bad-type.rs b/core/codegen/tests/ui-fail/typed-uri-bad-type.rs
index 05b24fb3..82f93101 100644
--- a/core/codegen/tests/ui-fail/typed-uri-bad-type.rs
+++ b/core/codegen/tests/ui-fail/typed-uri-bad-type.rs
@@ -1,7 +1,7 @@
 // normalize-stderr-test: "<(.*) as (.*)>" -> "$1 as $$TRAIT"
 // normalize-stderr-test: "and \d+ others" -> "and $$N others"
 
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/ui-fail/typed-uris-bad-params.rs b/core/codegen/tests/ui-fail/typed-uris-bad-params.rs
index 2baf5be9..2bde677c 100644
--- a/core/codegen/tests/ui-fail/typed-uris-bad-params.rs
+++ b/core/codegen/tests/ui-fail/typed-uris-bad-params.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/ui-fail/typed-uris-invalid-syntax.rs b/core/codegen/tests/ui-fail/typed-uris-invalid-syntax.rs
index 0c22cc17..34c71811 100644
--- a/core/codegen/tests/ui-fail/typed-uris-invalid-syntax.rs
+++ b/core/codegen/tests/ui-fail/typed-uris-invalid-syntax.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/codegen/tests/uri_display.rs b/core/codegen/tests/uri_display.rs
index b51d716a..bcd112d4 100644
--- a/core/codegen/tests/uri_display.rs
+++ b/core/codegen/tests/uri_display.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/http/src/cookies.rs b/core/http/src/cookies.rs
index 5a30b94d..c1158773 100644
--- a/core/http/src/cookies.rs
+++ b/core/http/src/cookies.rs
@@ -53,7 +53,7 @@ mod key {
 /// a handler to retrieve the value of a "message" cookie.
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::http::Cookies;
 ///
@@ -73,7 +73,7 @@ mod key {
 /// [private cookie]: Cookies::add_private()
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// use rocket::http::Status;
diff --git a/core/http/src/lib.rs b/core/http/src/lib.rs
index c27ed519..37f5d7e6 100644
--- a/core/http/src/lib.rs
+++ b/core/http/src/lib.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 #![recursion_limit="512"]
 
 #![warn(rust_2018_idioms)]
diff --git a/core/http/src/uri/from_uri_param.rs b/core/http/src/uri/from_uri_param.rs
index 4aa374f8..992f899b 100644
--- a/core/http/src/uri/from_uri_param.rs
+++ b/core/http/src/uri/from_uri_param.rs
@@ -155,7 +155,7 @@ use crate::uri::{self, UriPart, UriDisplay};
 /// With these implementations, the following typechecks:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # use std::fmt;
 /// use rocket::http::RawStr;
diff --git a/core/http/src/uri/uri_display.rs b/core/http/src/uri/uri_display.rs
index 153778fb..b41f399e 100644
--- a/core/http/src/uri/uri_display.rs
+++ b/core/http/src/uri/uri_display.rs
@@ -61,7 +61,7 @@ use crate::uri::{Uri, UriPart, Path, Query, Formatter};
 /// the following route:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #[get("/item/<id>?<track>")]
 /// fn get_item(id: i32, track: Option<String>) { /* .. */ }
@@ -70,7 +70,7 @@ use crate::uri::{Uri, UriPart, Path, Query, Formatter};
 /// A URI for this route can be generated as follows:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # type T = ();
 /// # #[get("/item/<id>?<track>")]
@@ -234,7 +234,7 @@ use crate::uri::{Uri, UriPart, Path, Query, Formatter};
 /// `UriDisplay` implementation is required.
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::http::RawStr;
 /// use rocket::request::FromParam;
@@ -432,7 +432,7 @@ impl<T: UriDisplay<Query>, E> UriDisplay<Query> for Result<T, E> {
 /// trait for the corresponding `UriPart`.
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #[get("/item/<id>?<track>")]
 /// fn get_item(id: i32, track: Option<u8>) { /* .. */ }
diff --git a/core/lib/benches/format-routing.rs b/core/lib/benches/format-routing.rs
index f71eca05..d20eb2ab 100644
--- a/core/lib/benches/format-routing.rs
+++ b/core/lib/benches/format-routing.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/lib/benches/ranked-routing.rs b/core/lib/benches/ranked-routing.rs
index d782ca79..df5716d2 100644
--- a/core/lib/benches/ranked-routing.rs
+++ b/core/lib/benches/ranked-routing.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 
 #[macro_use] extern crate rocket;
 
diff --git a/core/lib/benches/simple-routing.rs b/core/lib/benches/simple-routing.rs
index 27fef79d..8a1da0a6 100644
--- a/core/lib/benches/simple-routing.rs
+++ b/core/lib/benches/simple-routing.rs
@@ -1,4 +1,4 @@
-#![feature(proc_macro_hygiene)]
+#![feature(proc_macro_hygiene, async_await)]
 // #![feature(alloc_system)]
 // extern crate alloc_system;
 
diff --git a/core/lib/src/catcher.rs b/core/lib/src/catcher.rs
index 8fb1fa2b..bfc81101 100644
--- a/core/lib/src/catcher.rs
+++ b/core/lib/src/catcher.rs
@@ -36,7 +36,7 @@ use yansi::Color::*;
 /// declared using the `catch` decorator, as follows:
 ///
 /// ```rust
-/// #![feature(proc_macro_hygiene)]
+/// #![feature(proc_macro_hygiene, async_await)]
 ///
 /// #[macro_use] extern crate rocket;
 ///
@@ -78,16 +78,17 @@ impl Catcher {
     /// ```rust
     /// # #![allow(unused_variables)]
     /// use rocket::{Catcher, Request};
+    /// use rocket::handler::ErrorHandlerFuture;
     /// use rocket::response::{Result, Responder};
     /// use rocket::response::status::Custom;
     /// use rocket::http::Status;
     ///
-    /// fn handle_404<'r>(req: &'r Request) -> Result<'r> {
-    ///     let res = Custom(Status::NotFound, format!("404: {}", req.uri()));
-    ///     res.respond_to(req)
+    /// fn handle_404<'r>(req: &'r Request) -> ErrorHandlerFuture<'r> {
+    ///    let res = Custom(Status::NotFound, format!("404: {}", req.uri()));
+    ///    res.respond_to(req)
     /// }
     ///
-    /// fn handle_500<'r>(req: &'r Request) -> Result<'r> {
+    /// fn handle_500<'r>(req: &'r Request) -> ErrorHandlerFuture<'r> {
     ///     "Whoops, we messed up!".respond_to(req)
     /// }
     ///
diff --git a/core/lib/src/data/data.rs b/core/lib/src/data/data.rs
index caa32ddc..3b6fb12d 100644
--- a/core/lib/src/data/data.rs
+++ b/core/lib/src/data/data.rs
@@ -23,7 +23,7 @@ const PEEK_BYTES: usize = 512;
 /// specifying the `data = "<var>"` route parameter as follows:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # type DataGuard = rocket::data::Data;
 /// #[post("/submit", data = "<var>")]
diff --git a/core/lib/src/fairing/ad_hoc.rs b/core/lib/src/fairing/ad_hoc.rs
index dc160491..a2b9f1e2 100644
--- a/core/lib/src/fairing/ad_hoc.rs
+++ b/core/lib/src/fairing/ad_hoc.rs
@@ -117,12 +117,15 @@ impl AdHoc {
     /// # Example
     ///
     /// ```rust
+    /// # #![feature(async_await)]
     /// use rocket::fairing::AdHoc;
     ///
     /// // The no-op response fairing.
     /// let fairing = AdHoc::on_response("Dummy", |req, resp| {
-    ///     // do something with the request and pending response...
-    /// #   let (_, _) = (req, resp);
+    ///     Box::pin(async move {
+    ///         // do something with the request and pending response...
+    /// #       let (_, _) = (req, resp);
+    ///     })
     /// });
     /// ```
     pub fn on_response<F>(name: &'static str, f: F) -> AdHoc
diff --git a/core/lib/src/fairing/mod.rs b/core/lib/src/fairing/mod.rs
index d895e951..7ee7e14f 100644
--- a/core/lib/src/fairing/mod.rs
+++ b/core/lib/src/fairing/mod.rs
@@ -20,9 +20,10 @@
 //! write:
 //!
 //! ```rust
+//! # #![feature(async_await)]
 //! # use rocket::fairing::AdHoc;
 //! # let req_fairing = AdHoc::on_request("Request", |_, _| ());
-//! # let res_fairing = AdHoc::on_response("Response", |_, _| ());
+//! # let res_fairing = AdHoc::on_response("Response", |_, _| Box::pin(async move {}));
 //! let rocket = rocket::ignite()
 //!     .attach(req_fairing)
 //!     .attach(res_fairing);
@@ -206,7 +207,10 @@ pub use self::info_kind::{Info, Kind};
 /// path.
 ///
 /// ```rust
+/// # #![feature(async_await)]
+/// use std::future::Future;
 /// use std::io::Cursor;
+/// use std::pin::Pin;
 /// use std::sync::atomic::{AtomicUsize, Ordering};
 ///
 /// use rocket::{Request, Data, Response};
@@ -235,21 +239,23 @@ pub use self::info_kind::{Info, Kind};
 ///         }
 ///     }
 ///
-///     fn on_response(&self, request: &Request, response: &mut Response) {
-///         // Don't change a successful user's response, ever.
-///         if response.status() != Status::NotFound {
-///             return
-///         }
+///     fn on_response<'a, 'r>(&'a self, request: &'a Request<'r>, response: &'a mut Response<'r>) -> Pin<Box<dyn Future<Output=()> + Send + 'a>> {
+///         Box::pin(async move {
+///             // Don't change a successful user's response, ever.
+///             if response.status() != Status::NotFound {
+///                 return
+///             }
 ///
-///         if request.method() == Method::Get && request.uri().path() == "/counts" {
-///             let get_count = self.get.load(Ordering::Relaxed);
-///             let post_count = self.post.load(Ordering::Relaxed);
+///             if request.method() == Method::Get && request.uri().path() == "/counts" {
+///                 let get_count = self.get.load(Ordering::Relaxed);
+///                 let post_count = self.post.load(Ordering::Relaxed);
 ///
-///             let body = format!("Get: {}\nPost: {}", get_count, post_count);
-///             response.set_status(Status::Ok);
-///             response.set_header(ContentType::Plain);
-///             response.set_sized_body(Cursor::new(body));
-///         }
+///                 let body = format!("Get: {}\nPost: {}", get_count, post_count);
+///                 response.set_status(Status::Ok);
+///                 response.set_header(ContentType::Plain);
+///                 response.set_sized_body(Cursor::new(body));
+///             }
+///         })
 ///     }
 /// }
 /// ```
@@ -265,6 +271,9 @@ pub use self::info_kind::{Info, Kind};
 /// request guard.
 ///
 /// ```rust
+/// # #![feature(async_await)]
+/// # use std::future::Future;
+/// # use std::pin::Pin;
 /// # use std::time::{Duration, SystemTime};
 /// # use rocket::Outcome;
 /// # use rocket::{Request, Data, Response};
@@ -297,12 +306,14 @@ pub use self::info_kind::{Info, Kind};
 ///
 ///     /// Adds a header to the response indicating how long the server took to
 ///     /// process the request.
-///     fn on_response(&self, request: &Request, response: &mut Response) {
-///         let start_time = request.local_cache(|| TimerStart(None));
-///         if let Some(Ok(duration)) = start_time.0.map(|st| st.elapsed()) {
-///             let ms = duration.as_secs() * 1000 + duration.subsec_millis() as u64;
-///             response.set_raw_header("X-Response-Time", format!("{} ms", ms));
-///         }
+///     fn on_response<'a, 'r>(&'a self, request: &'a Request<'r>, response: &'a mut Response<'r>) -> Pin<Box<dyn Future<Output=()> + Send + 'a>> {
+///         Box::pin(async move {
+///             let start_time = request.local_cache(|| TimerStart(None));
+///             if let Some(Ok(duration)) = start_time.0.map(|st| st.elapsed()) {
+///                 let ms = duration.as_secs() * 1000 + duration.subsec_millis() as u64;
+///                 response.set_raw_header("X-Response-Time", format!("{} ms", ms));
+///             }
+///         })
 ///     }
 /// }
 ///
diff --git a/core/lib/src/handler.rs b/core/lib/src/handler.rs
index ab9fb048..08bdee31 100644
--- a/core/lib/src/handler.rs
+++ b/core/lib/src/handler.rs
@@ -42,15 +42,16 @@ pub type HandlerFuture<'r> = std::pin::Pin<Box<dyn Future<Output = Outcome<'r>>
 /// Such a handler might be written and used as follows:
 ///
 /// ```rust
+/// # #![feature(async_await)]
 /// # #[derive(Copy, Clone)] enum Kind { Simple, Intermediate, Complex, }
 /// use rocket::{Request, Data, Route, http::Method};
-/// use rocket::handler::{self, Handler, Outcome};
+/// use rocket::handler::{self, Handler, Outcome, HandlerFuture};
 ///
 /// #[derive(Clone)]
 /// struct CustomHandler(Kind);
 ///
 /// impl Handler for CustomHandler {
-///     fn handle<'r>(&self, req: &'r Request, data: Data) -> Outcome<'r> {
+///     fn handle<'r>(&self, req: &'r Request, data: Data) -> HandlerFuture<'r> {
 ///         match self.0 {
 ///             Kind::Simple => Outcome::from(req, "simple"),
 ///             Kind::Intermediate => Outcome::from(req, "intermediate"),
@@ -91,7 +92,7 @@ pub type HandlerFuture<'r> = std::pin::Pin<Box<dyn Future<Output = Outcome<'r>>
 /// managed state and a static route, as follows:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// # #[derive(Copy, Clone)]
@@ -198,10 +199,11 @@ impl<'r> Outcome<'r> {
     /// # Example
     ///
     /// ```rust
+    /// # #![feature(async_await)]
     /// use rocket::{Request, Data};
-    /// use rocket::handler::Outcome;
+    /// use rocket::handler::{Outcome, HandlerFuture};
     ///
-    /// fn str_responder(req: &Request, _: Data) -> Outcome<'static> {
+    /// fn str_responder<'r>(req: &'r Request, _: Data) -> HandlerFuture<'r> {
     ///     Outcome::from(req, "Hello, world!")
     /// }
     /// ```
@@ -253,10 +255,11 @@ impl<'r> Outcome<'r> {
     /// # Example
     ///
     /// ```rust
+    /// # #![feature(async_await)]
     /// use rocket::{Request, Data};
-    /// use rocket::handler::Outcome;
+    /// use rocket::handler::{Outcome, HandlerFuture};
     ///
-    /// fn str_responder(req: &Request, data: Data) -> Outcome<'static> {
+    /// fn str_responder<'r>(req: &'r Request, data: Data) -> HandlerFuture<'r> {
     ///     Outcome::from_or_forward(req, data, "Hello, world!")
     /// }
     /// ```
@@ -281,12 +284,15 @@ impl<'r> Outcome<'r> {
     /// # Example
     ///
     /// ```rust
+    /// # #![feature(async_await)]
     /// use rocket::{Request, Data};
-    /// use rocket::handler::Outcome;
+    /// use rocket::handler::{Outcome, HandlerFuture};
     /// use rocket::http::Status;
     ///
-    /// fn bad_req_route(_: &Request, _: Data) -> Outcome<'static> {
-    ///     Outcome::failure(Status::BadRequest)
+    /// fn bad_req_route<'r>(_: &'r Request, _: Data) -> HandlerFuture<'r> {
+    ///     Box::pin(async move {
+    ///         Outcome::failure(Status::BadRequest)
+    ///     })
     /// }
     /// ```
     #[inline(always)]
@@ -303,11 +309,14 @@ impl<'r> Outcome<'r> {
     /// # Example
     ///
     /// ```rust
+    /// # #![feature(async_await)]
     /// use rocket::{Request, Data};
-    /// use rocket::handler::Outcome;
+    /// use rocket::handler::{Outcome, HandlerFuture};
     ///
-    /// fn always_forward(_: &Request, data: Data) -> Outcome<'static> {
-    ///     Outcome::forward(data)
+    /// fn always_forward<'r>(_: &'r Request, data: Data) -> HandlerFuture<'r> {
+    ///     Box::pin(async move {
+    ///         Outcome::forward(data)
+    ///     })
     /// }
     /// ```
     #[inline(always)]
diff --git a/core/lib/src/lib.rs b/core/lib/src/lib.rs
index 316c929a..59c08f2f 100644
--- a/core/lib/src/lib.rs
+++ b/core/lib/src/lib.rs
@@ -48,7 +48,7 @@
 //! Then, add the following to the top of your `main.rs` file:
 //!
 //! ```rust
-//! #![feature(proc_macro_hygiene)]
+//! #![feature(proc_macro_hygiene, async_await)]
 //!
 //! #[macro_use] extern crate rocket;
 //! # #[get("/")] fn hello() { }
@@ -59,7 +59,7 @@
 //! write Rocket applications. Here's a simple example to get you started:
 //!
 //! ```rust
-//! #![feature(proc_macro_hygiene)]
+//! #![feature(proc_macro_hygiene, async_await)]
 //!
 //! #[macro_use] extern crate rocket;
 //!
diff --git a/core/lib/src/local/mod.rs b/core/lib/src/local/mod.rs
index 6265718a..0c66f90b 100644
--- a/core/lib/src/local/mod.rs
+++ b/core/lib/src/local/mod.rs
@@ -67,7 +67,7 @@
 //! consider the following complete "Hello, world!" application, with testing.
 //!
 //! ```rust
-//! #![feature(proc_macro_hygiene)]
+//! #![feature(proc_macro_hygiene, async_await)]
 //!
 //! #[macro_use] extern crate rocket;
 //!
diff --git a/core/lib/src/request/form/error.rs b/core/lib/src/request/form/error.rs
index 086be805..fdd1b3fc 100644
--- a/core/lib/src/request/form/error.rs
+++ b/core/lib/src/request/form/error.rs
@@ -50,7 +50,7 @@ pub enum FormDataError<'f, E> {
 /// # Example
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::request::{Form, FormError, FormDataError};
 ///
diff --git a/core/lib/src/request/form/form.rs b/core/lib/src/request/form/form.rs
index 5d13353f..a3053a8c 100644
--- a/core/lib/src/request/form/form.rs
+++ b/core/lib/src/request/form/form.rs
@@ -33,7 +33,7 @@ use crate::ext::AsyncReadExt as _;
 /// implements the `FromForm` trait:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::request::Form;
 /// use rocket::http::RawStr;
@@ -69,7 +69,7 @@ use crate::ext::AsyncReadExt as _;
 /// A handler that handles a form of this type can similarly by written:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #![allow(deprecated, unused_attributes)]
 /// # #[macro_use] extern crate rocket;
 /// # use rocket::request::Form;
@@ -122,7 +122,7 @@ impl<T> Form<T> {
     /// # Example
     ///
     /// ```rust
-    /// # #![feature(proc_macro_hygiene)]
+    /// # #![feature(proc_macro_hygiene, async_await)]
     /// # #[macro_use] extern crate rocket;
     /// use rocket::request::Form;
     ///
diff --git a/core/lib/src/request/form/from_form.rs b/core/lib/src/request/form/from_form.rs
index 08c55985..406f7d46 100644
--- a/core/lib/src/request/form/from_form.rs
+++ b/core/lib/src/request/form/from_form.rs
@@ -13,7 +13,7 @@ use crate::request::FormItems;
 /// validation.
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #![allow(deprecated, dead_code, unused_attributes)]
 /// # #[macro_use] extern crate rocket;
 /// #[derive(FromForm)]
@@ -30,7 +30,7 @@ use crate::request::FormItems;
 /// data via the `data` parameter and `Form` type.
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #![allow(deprecated, dead_code, unused_attributes)]
 /// # #[macro_use] extern crate rocket;
 /// # use rocket::request::Form;
diff --git a/core/lib/src/request/form/from_form_value.rs b/core/lib/src/request/form/from_form_value.rs
index 477639d2..2e083d9b 100644
--- a/core/lib/src/request/form/from_form_value.rs
+++ b/core/lib/src/request/form/from_form_value.rs
@@ -43,7 +43,7 @@ use crate::http::RawStr;
 /// according to its target type:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # type Size = String;
 /// #[get("/item?<id>&<size>")]
diff --git a/core/lib/src/request/form/lenient.rs b/core/lib/src/request/form/lenient.rs
index d25b3f1c..a70dcce2 100644
--- a/core/lib/src/request/form/lenient.rs
+++ b/core/lib/src/request/form/lenient.rs
@@ -31,7 +31,7 @@ use crate::http::uri::{Query, FromUriParam};
 /// handler:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::request::LenientForm;
 ///
@@ -67,7 +67,7 @@ impl<T> LenientForm<T> {
     /// # Example
     ///
     /// ```rust
-    /// # #![feature(proc_macro_hygiene)]
+    /// # #![feature(proc_macro_hygiene, async_await)]
     /// # #[macro_use] extern crate rocket;
     /// use rocket::request::LenientForm;
     ///
diff --git a/core/lib/src/request/from_request.rs b/core/lib/src/request/from_request.rs
index 8f603487..cd66d825 100644
--- a/core/lib/src/request/from_request.rs
+++ b/core/lib/src/request/from_request.rs
@@ -55,7 +55,7 @@ impl<S, E> IntoOutcome<S, (Status, E), ()> for Result<S, E> {
 /// guard.
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # use rocket::http::Method;
 /// # type A = Method; type B = Method; type C = Method; type T = ();
@@ -165,7 +165,7 @@ impl<S, E> IntoOutcome<S, (Status, E), ()> for Result<S, E> {
 /// `sensitive` handler.
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// use rocket::Outcome;
@@ -220,7 +220,7 @@ impl<S, E> IntoOutcome<S, (Status, E), ()> for Result<S, E> {
 /// routes (`admin_dashboard` and `user_dashboard`):
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # #[cfg(feature = "private-cookies")] mod inner {
 /// # use rocket::outcome::{IntoOutcome, Outcome};
@@ -283,7 +283,7 @@ impl<S, E> IntoOutcome<S, (Status, E), ()> for Result<S, E> {
 /// used, as illustrated below:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # #[cfg(feature = "private-cookies")] mod inner {
 /// # use rocket::outcome::{IntoOutcome, Outcome};
diff --git a/core/lib/src/request/param.rs b/core/lib/src/request/param.rs
index bcbdd9a5..931f5c2f 100644
--- a/core/lib/src/request/param.rs
+++ b/core/lib/src/request/param.rs
@@ -19,7 +19,7 @@ use crate::http::{RawStr, uri::{Segments, SegmentError}};
 /// handler for the dynamic `"/<id>"` path:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #[get("/<id>")]
 /// fn hello(id: usize) -> String {
@@ -54,7 +54,7 @@ use crate::http::{RawStr, uri::{Segments, SegmentError}};
 /// parameter as follows:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # use rocket::http::RawStr;
 /// #[get("/<id>")]
@@ -172,7 +172,7 @@ use crate::http::{RawStr, uri::{Segments, SegmentError}};
 /// dynamic path segment:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # use rocket::request::FromParam;
 /// # use rocket::http::RawStr;
diff --git a/core/lib/src/request/query.rs b/core/lib/src/request/query.rs
index d6a4d55b..af25bf69 100644
--- a/core/lib/src/request/query.rs
+++ b/core/lib/src/request/query.rs
@@ -8,7 +8,7 @@ use crate::request::{FormItems, FormItem, Form, LenientForm, FromForm};
 /// generation for every trailing query parameter, `<params..>` below:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// # use rocket::request::Form;
@@ -82,7 +82,7 @@ impl<'q> Iterator for Query<'q> {
 /// route:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::request::Form;
 ///
diff --git a/core/lib/src/request/state.rs b/core/lib/src/request/state.rs
index 54370a3d..f45cf559 100644
--- a/core/lib/src/request/state.rs
+++ b/core/lib/src/request/state.rs
@@ -22,7 +22,7 @@ use crate::http::Status;
 /// following example does just this:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::State;
 ///
@@ -87,7 +87,7 @@ use crate::http::Status;
 /// [`State::from()`] static method:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::State;
 ///
diff --git a/core/lib/src/response/flash.rs b/core/lib/src/response/flash.rs
index 2251156a..35a5689c 100644
--- a/core/lib/src/response/flash.rs
+++ b/core/lib/src/response/flash.rs
@@ -45,7 +45,7 @@ const FLASH_COOKIE_NAME: &str = "_flash";
 /// message on both the request and response sides.
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::response::{Flash, Redirect};
 /// use rocket::request::FlashMessage;
diff --git a/core/lib/src/response/redirect.rs b/core/lib/src/response/redirect.rs
index d891fdac..8d5017a1 100644
--- a/core/lib/src/response/redirect.rs
+++ b/core/lib/src/response/redirect.rs
@@ -26,7 +26,7 @@ use crate::http::Status;
 /// a route, _always_ use [`uri!`] to construct a valid [`Origin`]:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// use rocket::response::Redirect;
 ///
diff --git a/core/lib/src/response/responder.rs b/core/lib/src/response/responder.rs
index 18605960..a5e6ab0a 100644
--- a/core/lib/src/response/responder.rs
+++ b/core/lib/src/response/responder.rs
@@ -13,7 +13,7 @@ use crate::request::Request;
 /// as illustrated below with `T`:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// # type T = ();
 /// #
@@ -154,7 +154,7 @@ use crate::request::Request;
 /// following `Responder` implementation accomplishes this:
 ///
 /// ```rust
-/// # #![feature(proc_macro_hygiene)]
+/// # #![feature(proc_macro_hygiene, async_await)]
 /// # #[macro_use] extern crate rocket;
 /// #
 /// # #[derive(Debug)]
@@ -166,14 +166,16 @@ use crate::request::Request;
 /// use rocket::response::{self, Response, Responder};
 /// use rocket::http::ContentType;
 ///
-/// impl Responder<'_> for Person {
-///     fn respond_to(self, _: &Request) -> response::Result<'static> {
-///         Response::build()
-///             .sized_body(Cursor::new(format!("{}:{}", self.name, self.age)))
-///             .raw_header("X-Person-Name", self.name)
-///             .raw_header("X-Person-Age", self.age.to_string())
-///             .header(ContentType::new("application", "x-person"))
-///             .ok()
+/// impl Responder<'r> for Person {
+///     fn respond_to(self, _: &'r Request) -> response::ResultFuture<'r> {
+///         Box::pin(async move {
+///             Response::build()
+///                 .sized_body(Cursor::new(format!("{}:{}", self.name, self.age)))
+///                 .raw_header("X-Person-Name", self.name)
+///                 .raw_header("X-Person-Age", self.age.to_string())
+///                 .header(ContentType::new("application", "x-person"))
+///                 .ok()
+///         })
 ///     }
 /// }
 /// #
diff --git a/core/lib/src/rocket.rs b/core/lib/src/rocket.rs
index a1a3add3..9538a9d9 100644
--- a/core/lib/src/rocket.rs
+++ b/core/lib/src/rocket.rs
@@ -513,7 +513,7 @@ impl Rocket {
     /// dispatched to the `hi` route.
     ///
     /// ```rust
-    /// # #![feature(proc_macro_hygiene)]
+    /// # #![feature(proc_macro_hygiene, async_await)]
     /// # #[macro_use] extern crate rocket;
     /// #
     /// #[get("/world")]
@@ -535,10 +535,10 @@ impl Rocket {
     ///
     /// ```rust
     /// use rocket::{Request, Route, Data};
-    /// use rocket::handler::Outcome;
+    /// use rocket::handler::{HandlerFuture, Outcome};
     /// use rocket::http::Method::*;
     ///
-    /// fn hi<'r>(req: &'r Request, _: Data) -> Outcome<'r> {
+    /// fn hi<'r>(req: &'r Request, _: Data) -> HandlerFuture<'r> {
     ///     Outcome::from(req, "Hello!")
     /// }
     ///
@@ -585,7 +585,7 @@ impl Rocket {
     /// # Examples
     ///
     /// ```rust
-    /// # #![feature(proc_macro_hygiene)]
+    /// # #![feature(proc_macro_hygiene, async_await)]
     /// # #[macro_use] extern crate rocket;
     /// use rocket::Request;
     ///
@@ -641,7 +641,7 @@ impl Rocket {
     /// # Example
     ///
     /// ```rust
-    /// # #![feature(proc_macro_hygiene)]
+    /// # #![feature(proc_macro_hygiene, async_await)]
     /// # #[macro_use] extern crate rocket;
     /// use rocket::State;
     ///
@@ -678,7 +678,7 @@ impl Rocket {
     /// # Example
     ///
     /// ```rust
-    /// # #![feature(proc_macro_hygiene)]
+    /// # #![feature(proc_macro_hygiene, async_await)]
     /// # #[macro_use] extern crate rocket;
     /// use rocket::Rocket;
     /// use rocket::fairing::AdHoc;
@@ -819,7 +819,7 @@ impl Rocket {
     /// # Example
     ///
     /// ```rust
-    /// # #![feature(proc_macro_hygiene)]
+    /// # #![feature(proc_macro_hygiene, async_await)]
     /// # #[macro_use] extern crate rocket;
     /// use rocket::Rocket;
     /// use rocket::fairing::AdHoc;
@@ -875,7 +875,7 @@ impl Rocket {
     /// # Example
     ///
     /// ```rust
-    /// # #![feature(proc_macro_hygiene)]
+    /// # #![feature(proc_macro_hygiene, async_await)]
     /// # #[macro_use] extern crate rocket;
     /// use rocket::Rocket;
     /// use rocket::fairing::AdHoc;
diff --git a/core/lib/src/router/route.rs b/core/lib/src/router/route.rs
index 3ec2363c..0d062da3 100644
--- a/core/lib/src/router/route.rs
+++ b/core/lib/src/router/route.rs
@@ -108,8 +108,8 @@ impl Route {
     /// use rocket::Route;
     /// use rocket::http::Method;
     /// # use rocket::{Request, Data};
-    /// # use rocket::handler::Outcome;
-    /// # fn handler<'r>(request: &'r Request, _data: Data) -> Outcome<'r> {
+    /// # use rocket::handler::{Outcome, HandlerFuture};
+    /// # fn handler<'r>(request: &'r Request, _data: Data) -> HandlerFuture<'r> {
     /// #     Outcome::from(request, "Hello, world!")
     /// # }
     ///
@@ -158,8 +158,8 @@ impl Route {
     /// use rocket::Route;
     /// use rocket::http::Method;
     /// # use rocket::{Request, Data};
-    /// # use rocket::handler::Outcome;
-    /// # fn handler<'r>(request: &'r Request, _data: Data) -> Outcome<'r> {
+    /// # use rocket::handler::{Outcome, HandlerFuture};
+    /// # fn handler<'r>(request: &'r Request, _data: Data) -> HandlerFuture<'r> {
     /// #     Outcome::from(request, "Hello, world!")
     /// # }
     ///
@@ -208,9 +208,9 @@ impl Route {
     /// use rocket::Route;
     /// use rocket::http::Method;
     /// # use rocket::{Request, Data};
-    /// # use rocket::handler::Outcome;
+    /// # use rocket::handler::{Outcome, HandlerFuture};
     /// #
-    /// # fn handler<'r>(request: &'r Request, _data: Data) -> Outcome<'r> {
+    /// # fn handler<'r>(request: &'r Request, _data: Data) -> HandlerFuture<'r> {
     /// #     Outcome::from(request, "Hello, world!")
     /// # }
     ///
@@ -242,9 +242,9 @@ impl Route {
     /// use rocket::Route;
     /// use rocket::http::{Method, uri::Origin};
     /// # use rocket::{Request, Data};
-    /// # use rocket::handler::Outcome;
+    /// # use rocket::handler::{Outcome, HandlerFuture};
     /// #
-    /// # fn handler<'r>(request: &'r Request, _data: Data) -> Outcome<'r> {
+    /// # fn handler<'r>(request: &'r Request, _data: Data) -> HandlerFuture<'r> {
     /// #     Outcome::from(request, "Hello, world!")
     /// # }
     ///