If you don't have Rust yet, we recommend you use `rustup` to manage your Rust installation. The [official rust guide][rustguide] has a wonderful section on getting started.
Actix Web currently has a minimum supported Rust version (MSRV) of {{<rust-version"actix-web">}}. Running `rustup update` will ensure you have the latest and greatest Rust version available. As such, this guide assumes you are running Rust {{<rust-version"actix-web">}} or later.
Request handlers use async functions that accept zero or more parameters. These parameters can be extracted from a request (see `FromRequest` trait) and returns a type that can be converted into an `HttpResponse` (see `Responder` trait):
Notice that some of these handlers have routing information attached directly using the built-in macros. These allow you to specify the method and path that the handler should respond to. You will see below how to register `manual_hello` (i.e. routes that do not use a routing macro).
Next, create an `App` instance and register the request handlers. Use `App::service` for the handlers using routing macros and `App::route` for manually routed handlers, declaring the path and method. Finally, the app is started inside an `HttpServer` which will serve incoming requests using your `App` as an "application factory".
That's it! Compile and run the program with `cargo run`. The `#[actix_web::main]` macro executes the async main function within the actix runtime. Now you can go to `http://127.0.0.1:8080/` or any of the other routes you defined to see the results.
