--- title: Getting Started menu: docs_basics weight: 130 --- # Getting Started Let’s write our first `actix-web` application! ## Hello, world! Start by creating a new binary-based Cargo project and changing into the new directory: ```bash cargo new hello-world cd hello-world ``` Now, add `actix-web` as dependencies of your project by ensuring your `Cargo.toml` contains the following: ```ini [dependencies] actix-web = "{{< actix-version "actix-web" >}}" ``` In order to implement a web server, we first need to create a request handler. A request handler is a function that accepts zero or more parameters that can be extracted from a request (ie, `impl FromRequest`) and returns a type that can be converted into an `HttpResponse` (ie, `impl Responder`): {{< include-example example="getting-started" section="setup" >}} Next, create an `App` instance and register the request handler with the application's `route` on a *path* and with a particular *HTTP method*. After that, the application instance can be used with `HttpServer` to listen for incoming connections. The server accepts a function that should return an application factory. {{< include-example example="getting-started" section="main" >}} That's it! Now, compile and run the program with `cargo run`. Head over to ``http://localhost:8088/`` to see the results. ### Alternative syntax You might prefer the alternative syntax provided by [actix-web-codegen] which allows you to specify the routes above your functions like so: {{< include-example example="getting-started" section="alternative">}} You can then declare this function using `service()`: ```rust App::new() .service(index3) ``` For consistency reasons, this documentation only uses the regular syntax shown at the beginning of this page. However, if you prefer this syntax you should feel free to use it any time you declare a route as it's only syntactic sugar. ### Auto-reloading If you want, you can have an automatically reloading server during development that recompiles on demand. This isn't necessary, but it makes rapid prototyping more convenient as you can see changes instantly upon saving. To see how this can be accomplished, have a look at the [autoreload pattern][autoload]. [actix-web-codegen]: https://docs.rs/actix-web-codegen/0.1.2/actix_web_codegen/ [autoload]: ../autoreload/