diff --git a/src/app.rs b/src/app.rs
index b4b952734..10868d18d 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -122,9 +122,10 @@ impl<T> App<T> {
         self.app_data(Data::new(data))
     }
 
-    /// Add application data factory. This function is similar to `.data()` but it accepts a
-    /// "data factory". Data values are constructed asynchronously during application
-    /// initialization, before the server starts accepting requests.
+    /// Add application data factory that resolves asynchronously.
+    ///
+    /// Data items are constructed during application initialization, before the server starts
+    /// accepting requests.
     pub fn data_factory<F, Out, D, E>(mut self, data: F) -> Self
     where
         F: Fn() -> Out + 'static,
@@ -150,6 +151,7 @@ impl<T> App<T> {
             }
             .boxed_local()
         }));
+
         self
     }
 
@@ -200,11 +202,9 @@ impl<T> App<T> {
     ///     "Welcome!"
     /// }
     ///
-    /// fn main() {
-    ///     let app = App::new()
-    ///         .route("/test1", web::get().to(index))
-    ///         .route("/test2", web::post().to(|| HttpResponse::MethodNotAllowed()));
-    /// }
+    /// let app = App::new()
+    ///     .route("/test1", web::get().to(index))
+    ///     .route("/test2", web::post().to(|| HttpResponse::MethodNotAllowed()));
     /// ```
     pub fn route(self, path: &str, mut route: Route) -> Self {
         self.service(
@@ -243,13 +243,11 @@ impl<T> App<T> {
     ///     "Welcome!"
     /// }
     ///
-    /// fn main() {
-    ///     let app = App::new()
-    ///         .service(
-    ///             web::resource("/index.html").route(web::get().to(index)))
-    ///         .default_service(
-    ///             web::route().to(|| HttpResponse::NotFound()));
-    /// }
+    /// let app = App::new()
+    ///     .service(
+    ///         web::resource("/index.html").route(web::get().to(index)))
+    ///     .default_service(
+    ///         web::route().to(|| HttpResponse::NotFound()));
     /// ```
     ///
     /// It is also possible to use static files as default service.
@@ -257,14 +255,12 @@ impl<T> App<T> {
     /// ```
     /// use actix_web::{web, App, HttpResponse};
     ///
-    /// fn main() {
-    ///     let app = App::new()
-    ///         .service(
-    ///             web::resource("/index.html").to(|| HttpResponse::Ok()))
-    ///         .default_service(
-    ///             web::to(|| HttpResponse::NotFound())
-    ///         );
-    /// }
+    /// let app = App::new()
+    ///     .service(
+    ///         web::resource("/index.html").to(|| HttpResponse::Ok()))
+    ///     .default_service(
+    ///         web::to(|| HttpResponse::NotFound())
+    ///     );
     /// ```
     pub fn default_service<F, U>(mut self, svc: F) -> Self
     where
diff --git a/src/app_service.rs b/src/app_service.rs
index 4e84cb201..e0d424390 100644
--- a/src/app_service.rs
+++ b/src/app_service.rs
@@ -236,6 +236,7 @@ where
 }
 
 pub struct AppRoutingFactory {
+    #[allow(clippy::type_complexity)]
     services: Rc<
         [(
             ResourceDef,
diff --git a/src/config.rs b/src/config.rs
index 9e77c0f96..cfa9a4ca3 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -24,6 +24,7 @@ pub struct AppService {
     config: AppConfig,
     root: bool,
     default: Rc<HttpNewService>,
+    #[allow(clippy::type_complexity)]
     services: Vec<(
         ResourceDef,
         HttpNewService,
@@ -48,6 +49,7 @@ impl AppService {
         self.root
     }
 
+    #[allow(clippy::type_complexity)]
     pub(crate) fn into_services(
         self,
     ) -> (
diff --git a/src/guard.rs b/src/guard.rs
index d5c585c1b..db7f06987 100644
--- a/src/guard.rs
+++ b/src/guard.rs
@@ -15,14 +15,12 @@
 //! ```
 //! use actix_web::{web, http, dev, guard, App, HttpResponse};
 //!
-//! fn main() {
-//!     App::new().service(web::resource("/index.html").route(
-//!         web::route()
-//!              .guard(guard::Post())
-//!              .guard(guard::fn_guard(|head| head.method == http::Method::GET))
-//!              .to(|| HttpResponse::MethodNotAllowed()))
-//!     );
-//! }
+//! App::new().service(web::resource("/index.html").route(
+//!     web::route()
+//!          .guard(guard::Post())
+//!          .guard(guard::fn_guard(|head| head.method == http::Method::GET))
+//!          .to(|| HttpResponse::MethodNotAllowed()))
+//! );
 //! ```
 
 #![allow(non_snake_case)]
@@ -53,16 +51,14 @@ impl Guard for Rc<dyn Guard> {
 /// ```
 /// use actix_web::{guard, web, App, HttpResponse};
 ///
-/// fn main() {
-///     App::new().service(web::resource("/index.html").route(
-///         web::route()
-///             .guard(
-///                 guard::fn_guard(
-///                     |req| req.headers()
-///                              .contains_key("content-type")))
-///             .to(|| HttpResponse::MethodNotAllowed()))
-///     );
-/// }
+/// App::new().service(web::resource("/index.html").route(
+///     web::route()
+///         .guard(
+///             guard::fn_guard(
+///                 |req| req.headers()
+///                          .contains_key("content-type")))
+///         .to(|| HttpResponse::MethodNotAllowed()))
+/// );
 /// ```
 pub fn fn_guard<F>(f: F) -> impl Guard
 where
@@ -96,13 +92,11 @@ where
 /// ```
 /// use actix_web::{web, guard, App, HttpResponse};
 ///
-/// fn main() {
-///     App::new().service(web::resource("/index.html").route(
-///         web::route()
-///              .guard(guard::Any(guard::Get()).or(guard::Post()))
-///              .to(|| HttpResponse::MethodNotAllowed()))
-///     );
-/// }
+/// App::new().service(web::resource("/index.html").route(
+///     web::route()
+///          .guard(guard::Any(guard::Get()).or(guard::Post()))
+///          .to(|| HttpResponse::MethodNotAllowed()))
+/// );
 /// ```
 pub fn Any<F: Guard + 'static>(guard: F) -> AnyGuard {
     AnyGuard(vec![Box::new(guard)])
@@ -135,14 +129,12 @@ impl Guard for AnyGuard {
 /// ```
 /// use actix_web::{guard, web, App, HttpResponse};
 ///
-/// fn main() {
-///     App::new().service(web::resource("/index.html").route(
-///         web::route()
-///             .guard(
-///                 guard::All(guard::Get()).and(guard::Header("content-type", "text/plain")))
-///             .to(|| HttpResponse::MethodNotAllowed()))
-///     );
-/// }
+/// App::new().service(web::resource("/index.html").route(
+///     web::route()
+///         .guard(
+///             guard::All(guard::Get()).and(guard::Header("content-type", "text/plain")))
+///         .to(|| HttpResponse::MethodNotAllowed()))
+/// );
 /// ```
 pub fn All<F: Guard + 'static>(guard: F) -> AllGuard {
     AllGuard(vec![Box::new(guard)])
diff --git a/src/handler.rs b/src/handler.rs
index 647606890..ea6855c7f 100644
--- a/src/handler.rs
+++ b/src/handler.rs
@@ -31,8 +31,8 @@ use crate::{
 /// The first thing to note is that [`FromRequest`] is implemented for tuples (up to 12 in length).
 ///
 /// Secondly, the `Handler` trait is implemented for functions (up to an [arity] of 12) in a way
-/// that aligns their parameter positions with a corresponding tuple of types (becoming the `T` type
-/// parameter in this trait's implementation).
+/// that aligns their parameter positions with a corresponding tuple of types (becoming the `Args`
+/// type parameter for this trait).
 ///
 /// Thanks to Rust's type system, Actix Web can infer the function parameter types. During the
 /// extraction step, the parameter types are described as a tuple type, [`from_request`] is run on
@@ -78,12 +78,12 @@ use crate::{
 /// [arity]: https://en.wikipedia.org/wiki/Arity
 /// [`from_request`]: FromRequest::from_request
 /// [on_unimpl]: https://github.com/rust-lang/rust/issues/29628
-pub trait Handler<T, R>: Clone + 'static
+pub trait Handler<Args, R>: Clone + 'static
 where
     R: Future,
     R::Output: Responder,
 {
-    fn call(&self, args: T) -> R;
+    fn call(&self, args: Args) -> R;
 }
 
 pub(crate) fn handler_service<F, Args, R>(handler: F) -> BoxedHttpServiceFactory
diff --git a/src/lib.rs b/src/lib.rs
index 3462ae90b..5f5b915b7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -66,7 +66,6 @@
 
 #![deny(rust_2018_idioms, nonstandard_style)]
 #![warn(future_incompatible)]
-#![allow(clippy::needless_doctest_main, clippy::type_complexity)]
 #![doc(html_logo_url = "https://actix.rs/img/logo.png")]
 #![doc(html_favicon_url = "https://actix.rs/favicon.ico")]
 
diff --git a/src/middleware/compress.rs b/src/middleware/compress.rs
index af4a107e3..d3cdf5763 100644
--- a/src/middleware/compress.rs
+++ b/src/middleware/compress.rs
@@ -113,6 +113,7 @@ where
 {
     type Response = ServiceResponse<EitherBody<Encoder<B>>>;
     type Error = Error;
+    #[allow(clippy::type_complexity)]
     type Future = Either<CompressResponse<S, B>, Ready<Result<Self::Response, Self::Error>>>;
 
     actix_service::forward_ready!(service);
diff --git a/src/resource.rs b/src/resource.rs
index c6c8a5b89..f0c6f6d7c 100644
--- a/src/resource.rs
+++ b/src/resource.rs
@@ -131,15 +131,13 @@ where
     /// ```
     /// use actix_web::{web, guard, App, HttpResponse};
     ///
-    /// fn main() {
-    ///     let app = App::new().service(
-    ///         web::resource("/").route(
-    ///             web::route()
-    ///                 .guard(guard::Any(guard::Get()).or(guard::Put()))
-    ///                 .guard(guard::Header("Content-Type", "text/plain"))
-    ///                 .to(|| HttpResponse::Ok()))
-    ///     );
-    /// }
+    /// let app = App::new().service(
+    ///     web::resource("/").route(
+    ///         web::route()
+    ///             .guard(guard::Any(guard::Get()).or(guard::Put()))
+    ///             .guard(guard::Header("Content-Type", "text/plain"))
+    ///             .to(|| HttpResponse::Ok()))
+    /// );
     /// ```
     ///
     /// Multiple routes could be added to a resource. Resource object uses
diff --git a/src/scope.rs b/src/scope.rs
index c3bab8f7e..176e0d5a0 100644
--- a/src/scope.rs
+++ b/src/scope.rs
@@ -469,6 +469,7 @@ where
 }
 
 pub struct ScopeFactory {
+    #[allow(clippy::type_complexity)]
     services: Rc<
         [(
             ResourceDef,
diff --git a/src/server.rs b/src/server.rs
index b2ff423f1..ed0c965b3 100644
--- a/src/server.rs
+++ b/src/server.rs
@@ -63,6 +63,7 @@ where
     backlog: u32,
     sockets: Vec<Socket>,
     builder: ServerBuilder,
+    #[allow(clippy::type_complexity)]
     on_connect_fn: Option<Arc<dyn Fn(&dyn Any, &mut Extensions) + Send + Sync>>,
     _phantom: PhantomData<(S, B)>,
 }