@pyreon/runtime-server

Server-side rendering for Pyreon. Renders VNode trees to HTML strings or Web-standard ReadableStream chunks with Suspense streaming support.

Install

bun add @pyreon/runtime-server

Quick Start

import { renderToString } from "@pyreon/runtime-server"

function App() {
  return <h1>Hello from SSR</h1>
}

const html = await renderToString(<App />)
// "<h1>Hello from SSR</h1>"

API

renderToString(vnode)

Render a VNode tree to a complete HTML string. Returns Promise<string>. Async components are awaited. Each call gets an isolated context stack.

renderToStream(vnode)

Render a VNode tree to a ReadableStream<string> for progressive HTML streaming. Synchronous subtrees are flushed immediately. Suspense boundaries are streamed out-of-order: the fallback is emitted first, then resolved children are sent as <template> elements with inline swap scripts.

import { renderToStream } from "@pyreon/runtime-server"

const stream = renderToStream(<App />)
return new Response(stream, {
  headers: { "Content-Type": "text/html" },
})

runWithRequestContext(fn)

Run an async function with a fresh, isolated context stack and store registry. Useful for calling Pyreon APIs (e.g. useHead, route loader prefetching) outside of renderToString while maintaining per-request isolation.

import { runWithRequestContext } from "@pyreon/runtime-server"

const result = await runWithRequestContext(async () => {
  // Pyreon context and stores are isolated to this call
  return await prefetchLoaderData(url)
})

configureStoreIsolation(registryProvider)

Wire up per-request store isolation for concurrent SSR. Call once at server startup with a function that hooks your store registry into the request-scoped AsyncLocalStorage. Prevents store state from leaking between requests.

import { configureStoreIsolation } from "@pyreon/runtime-server"

configureStoreIsolation(provider => {
  // Wire your store registry to use the per-request provider
})

Behavior Notes

• Signal accessors are called synchronously to snapshot their current value. No effects are created on the server.
• Async component functions (async function Component()) are fully supported.
• Context isolation uses AsyncLocalStorage internally. Each renderToString and renderToStream call gets its own context stack.
• HTML output is escaped. Event handlers and custom directives (on*, n-*) are omitted. URL attributes are sanitized against javascript: and data: URIs.