> For the complete documentation index, see [llms.txt](https://docs.aurelia.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.aurelia.io/~/revisions/NShYVVc01DvYc5bgBiwq/getting-to-know-aurelia/app-configuration-and-startup.md). # App configuration and startup ## Application Startup Aurelia allows you to configure the application startup in a couple of different ways. A quick setup where some defaults are assumed and a verbose setup where you can configure some of the framework-specific behaviors. ### Quick startup The quick startup approach is what most developers will choose. ```typescript import { RouterConfiguration } from '@aurelia/router'; import Aurelia, { StyleConfiguration } from 'aurelia'; import { MyRootComponent } from './my-root-component'; // By default host to element name ( for MyRootComponent), // or if is absent. Aurelia.app(MyRootComponent).start(); // Or load additional Aurelia features Aurelia .register( RouterConfiguration.customize({ useUrlFragmentHash: false }) ) .app(MyRootComponent) .start(); // Or host to Aurelia .register( RouterConfiguration.customize({ useUrlFragmentHash: false }) ) .app({ component: MyRootComponent, host: document.querySelector('my-start-tag') }) .start(); ``` ### Verbose Startup To start an Aurelia application, create a `new Aurelia()` object with a target `host` and a root `component` and call `start()`. ```typescript import Aurelia, { StandardConfiguration } from 'aurelia'; import { ShellComponent } from './shell'; new Aurelia() .register(StandardConfiguration) .app({ host: document.querySelector('body'), component: ShellComponent }) .start(); ``` In most instances, you will not use the verbose approach to starting your Aurelia applications. The verbose approach is more aimed at developers integrating Aurelia into existing web applications and views. ## Register a globally available custom element ### Registering a single element To make a custom element globally available to your application, pass the custom element constructor to the `.register()` method on your Aurelia app. ```typescript import { CardCustomElement } from './components/card'; // When using quick startup Aurelia .register(...) .register(CardCustomElement); .app({ ... }) .start(); // When using verbose startup new Aurelia() .register(...) .register(CardCustomElement) .app({ ... }) .start(); ``` ### Register a set of elements If you have a package that exports all your custom elements, you can pass the entire package to the `.register()` method on your Aurelia app. src/components/index.ts: ```typescript export { CardCustomElement } from './card'; export { CollapseCustomElement } from './collapse'; ``` src/main.ts: ```typescript import * as globalComponents from './components'; // When using quick startup Aurelia .register(...) .register(globalComponents) .app({ ... }) .start(); // When using verbose startup new Aurelia() .register(...) .register(globalComponents) .app({ ... }) .start(); ``` --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.aurelia.io/~/revisions/NShYVVc01DvYc5bgBiwq/getting-to-know-aurelia/app-configuration-and-startup.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.