Crate fob_plugin_astro 

Rolldown plugin for Astro components

This plugin extracts and processes frontmatter and <script> blocks from Astro components, making them available to the bundler as JavaScript/TypeScript modules.

Architecture

.astro file → load() hook → AstroExtractor → Extract frontmatter + scripts → JS/TS → Rolldown

Why the load hook?

We use the load hook (not transform) because:

• Astro components aren’t valid JavaScript/TypeScript that Rolldown can parse
• We must intercept files before Rolldown’s parser runs
• The load hook is designed for custom file formats
• We return extracted JavaScript with the appropriate ModuleType

Handling Frontmatter and Scripts

Astro components can contain:

• One frontmatter block at the start (delimited by ---, TypeScript by default)
• Multiple <script> tags in the template (JavaScript by default)

Frontmatter runs on the server during build/SSR, while script tags run in the browser. When both exist, we combine them with frontmatter first, as it executes during the component’s module loading phase.

Example Usage

use fob_plugin_astro::FobAstroPlugin;
use std::sync::Arc;

let plugin = Arc::new(FobAstroPlugin::new());
// Add to your Rolldown bundler configuration

Structs

FobAstroPlugin

Rolldown plugin that extracts JavaScript/TypeScript from Astro components