Lustre examples directory

Each of the examples in this directory is a self-contained, complete Gleam app that demonstrates a particular feature or concept of the library. For newcomers, we recommend looking through them in order, as each example tends to build on the previous ones. Feel free to jump in to any example that interests you, though!

01-basics

These examples cover the fundamentals of Lustre such as setting up an application or rendering elements that can handle events.

• 01-hello-world is a simple example to just get something on the screen.

• 02-attributes demonstrates how to add attributes to HTML elements.

• 03-view-functions shows how to organize your view code into functions.

• 04-keyed-elements explains how to use keyed elements for optimized rendering.

• 05-fragments demonstrates how to use fragments to group elements.

• 06-flags shows how to pass initialization data to your Lustre application.

02-inputs

Handling inputs and interactive elements is an important part of any application! These examples cover how to work with user input within the Model-View-Update architecture.

• 01-controlled-inputs demonstrates the most common way to handle <input /> elements in Lustre.

• 02-decoding-events shows you how to write your own event handlers and decoders, instead of relying on the ones provided by lustre/event.

• 03-debouncing demonstrates how to implement debouncing for user inputs.

• 04-forms shows how to work with form submissions in Lustre.

03-effects

These examples demonstrate how to handle side effects in Lustre applications. Side effects are actions that read from or affect change to the outside world, such as making HTTP requests, manipulating the DOM, or working with timers.

• 01-http-requests demonstrates how side effects are handled in Lustre, using HTTP requests as an example.

• 02-random shows how to generate random values in a Lustre application.

• 03-timers demonstrates working with timers and intervals.

• 04-local-storage shows how to interact with browser local storage.

• 05-dom-effects demonstrates direct DOM manipulation effects.

• 06-optimistic-requests shows how to implement optimistic UI updates.

04-applications

Examples related to building full Lustre single-page applications (SPAs), covering concepts like routing, page organisation, and state hydration.

• 01-routing shows you how to set up routing and navigation between pages.

• 04-hydration demonstrates client-side hydration of server-rendered Lustre apps.

05-components

These examples demonstrate how to create reusable components in Lustre. Components are an advanced feature that let you construct real Custom Elements that have access to native features like shadow DOM, slotted content, and custom attributes and events.

• 01-basic-setup introduces web components with Lustre.

• 02-attributes-and-events shows how to handle attributes and events in components.

• 03-slots demonstrates using slots in web components.

06-server-components

Lustre components can also be run in real-time on the server, allowing you to take a part of your application and move it closer to the data source. These examples demonstrate Lustre’s server components.

• 01-basic-setup introduces server components in Lustre.

• 02-attributes-and-events shows working with attributes and events in server components.

• 03-event-include demonstrates how to include events in server components.

• 04-multiple-clients shows how to handle multiple clients connected to the same server component runtime.

• 5-publish-subscribe shows how to handle multiple server components using publish-subscribe to communicate.

Getting help

If you’re having trouble with Lustre or not sure what the right way to do something is, the best place to get help is the Gleam Discord server. You could also open an issue on the Lustre GitHub repository.

While our docs are still a work in progress, the official Elm guide is also a great resource for learning about the Model-View-Update architecture and the kinds of patterns that Lustre is built around.