Declarative Shadow DOM

In this article, I will first highlight the challenge that has made using web components, specifically the shadow DOM, a non-starter for many projects. But then, we will explore an evolution of shadow DOM that is already well-supported in modern browsers, known as declarative shadow DOM, and learn how it breaks down one of the final obstacles and enables us to write reusable, isolated web components that can be server-side rendered or used as part of a statically generated website.

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Web components have always promised reusable, isolated, and standards-based solutions for building modern web applications. Yet, challenges like server-side rendering (SSR), static site generation (SSG), performance, and accessibility have often kept developers reliant on frameworks and custom solutions. Declarative Shadow DOM bridges these gaps, unlocking the full potential of web components for the modern web platform.

By simplifying integration with SSR and SSG, Declarative Shadow DOM makes web components more approachable, scalable, and powerful across a variety of tools and frameworks. Whether you’re working with JavaScript-based solutions like Astro or React, or traditional server-side frameworks like Django or Laravel, the benefits are clear: faster load times, improved developer experience, and seamless browser parsing of components.

Source: Declarative Shadow DOM | 12 Days of Web