Framework Compatibility

howth can run modern JavaScript frameworks directly in its native V8 runtime, without requiring Node.js.

Compatibility Matrix

Framework	Status	Notes
Next.js	✅ Working	Static pages, API routes, SSR
SvelteKit	✅ Working	Full SSR support
Remix	✅ Working	Full SSR with loaders and actions
Express	✅ Working	Full support via node:http
Fastify	✅ Working	Full support via node:http
Hono	✅ Working	Full support

Next.js

Next.js works with howth out of the box.

Setup

1. Build your app:

npm run build

2. Run with howth:

howth run node_modules/next/dist/bin/next -- start

What Works

• Static pages
• Server-side rendering (SSR)
• API routes (pages/api/*)
• Dynamic routes
• Static generation

SvelteKit

SvelteKit works with howth using @sveltejs/adapter-node.

Setup

1. Install the adapter:

npm install @sveltejs/adapter-node

2. Configure svelte.config.js:

import adapter from '@sveltejs/adapter-node';

export default {
  kit: {
    adapter: adapter()
  }
};

3. Build your app:

npm run build

4. Run with howth:

howth run build/index.js

What Works

• Server-side rendering (SSR)
• Routing and page navigation
• API routes (+server.js)
• Form actions
• Streaming responses
• Custom URL protocols (e.g., sveltekit-internal://)

Remix

Remix works with howth using @remix-run/express.

Setup

1. Use the Express adapter:

npm install @remix-run/express @remix-run/node express

2. Create a server entry point (server.js):

const express = require("express");
const { createRequestHandler } = require("@remix-run/express");

const app = express();
app.all("*", createRequestHandler({ build: require("./build") }));
app.listen(3000);

3. Build and run:

npm run build
howth run server.js

What Works

• Server-side rendering (SSR)
• Loaders and loader data
• Actions and form handling
• File-based routing
• Streaming responses (React 18 renderToPipeableStream)

Express

Express works out of the box with howth's node:http implementation.

import express from 'express';

const app = express();

app.get('/', (req, res) => {
  res.send('Hello from howth!');
});

app.listen(3000, () => {
  console.log('Server running at http://localhost:3000');
});

Run with:

howth run server.js

Fastify

Fastify works with howth's node:http implementation.

import Fastify from 'fastify';

const fastify = Fastify();

fastify.get('/', async () => {
  return { hello: 'world' };
});

await fastify.listen({ port: 3000 });

API Features Required by Frameworks

The following APIs were added to support framework compatibility:

API	Frameworks Using It
Request.signal	Remix
TextEncoder.encodeInto()	Remix (React SSR streaming)
Named exports for node:* modules	SvelteKit
Custom URL protocols	SvelteKit
AbortController/AbortSignal	Remix, SvelteKit
ReadableStream/WritableStream	Remix, SvelteKit