vite-plugin-preact-progressive

Functions

• default

default

Build wiring for "use client" boundaries.

How the plugin converts "use client" source into deployable chunks. Each environment transforms its own way, with the client stripping directives and the server rewriting references. The server transform discovers client modules and the client compile emits them as on-demand chunks. A final pass patches server output placeholders with real chunk URLs.

• The client environment emits every discovered client module as a chunk.
• Server environments build before the client in buildApp.
• Files containing the text use client transform, and everything else passes through untouched.

Placeholders

Production server transforms cannot know chunk URLs, since the client compiles after the server. References carry content-hashed placeholders instead, derived from the module path relative to project root:

• __PP_MOD__<sha256> for the module chunk URL.
• __PP_DEPS__<hash> for the chunk dependencies to preload ($deps).

Dev skips placeholders. Module URLs resolve from the module graph, with deps staying empty.

Client emission

Every discovered client module emits as a chunk with preserveSignature: "exports-only". The build needs build.manifest: true, and the post-build pass maps module paths to chunk files through .vite/manifest.json, following transitive imports for deps.

Rewrite pass

All environments compile first, then the plugin rewrites recorded server output files in place. MOD tokens become the quoted chunk URL. DEPS tokens become the quoted dependency array, replacing the whole surrounding array literal so the list stays flat. The first unresolvable token fails the build.

Requirements

• build.manifest: true on the client environment. Without .vite/manifest.json the plugin errors.
• emitAssets: true on server environments using ?assets= imports for entry CSS/URLs.
• Server output files patch in place after both environments build. A missing manifest entry or unknown client-module hash errors.

Stylesheet handling relies on emitAssets plus the fullstack ?assets module. On Rsbuild instead, see rsbuild-plugin-preact-progressive, which targets the same wire format on a different toolchain.

Server-side decoding (virtual:server-load-module)

The encoder only carries enough information to load client references in browser builds. To run the decoder on the server (prerendering an island to HTML and its payload in a single pass, or round-tripping richer information for server actions), import virtual:server-load-module from a server environment. It exports a loadModule implementation for the decoder which maps each encoded client module id to its server equivalent and loads it:

import { loadModule } from "virtual:server-load-module";
import { Decoder } from "preact-progressive/decoder";

const decoder = new Decoder(namespace, { loadModule });
await decoder.preload(row);
const decoded = decoder.decode(row);

The server transform registers every reference's implementation on globalThis.__pp_server_modules when its module evaluates, so the loader resolves synchronously: decode() hands out the real implementation without suspending, with no per-project enumeration and no reliance on bundled export names. Available in server environments only.

Constants

• VIRTUAL_SERVER_LOAD_MODULE

VIRTUAL_SERVER_LOAD_MODULE

Virtual module exporting a server-side loadModule for the Decoder.

Types

• Options

Options