Cossack is designed to be runtime-agnostic. The core framework logic is decoupled from the underlying server environment using the CossackServerRuntime interface.

We currently support two official adapters:

1. Cloudflare Workers (Default)

This is the primary and most feature-complete adapter, leveraging Cloudflare's unique capabilities.

• Runtime: Cloudflare Workers
• Transport: Cloudflare Durable Objects (WebSockets)
• State Persistence: Automatic via Durable Object Storage.
• Scalability: Durable Objects provide strong consistency and global uniqueness for component instances.

Usage

This adapter is used by default when creating a new Cossack app. The application entry point (src/index.ts) exports a standard Worker module:

import { createApp, AppDurableObject } from '@cossackframework/framework';

const app = createApp();

export { AppDurableObject };
export default {
  fetch: app.fetch,
};

2. Node.js Adapter

This adapter allows you to run Cossack applications on a standard Node.js server (e.g., in a container, on a VPS, or locally).

• Runtime: Node.js (>= 20)
• Transport: ws library (WebSockets)
• State Persistence: Memory Only. State is lost when the server process restarts.
• Scalability: Suitable for single-instance deployments or sticky-session clusters.

Usage

To use the Node.js adapter, your application entry point must initialize a Node.js HTTP server and attach the CossackNodeAdapter.

import { serve } from '@hono/node-server';
import { CossackNodeAdapter } from '@cossackframework/node-adapter';
import { createApp } from './router';
// Import your pages/components registry logic here

const app = createApp();
const componentRegistry = ...; // Map of ComponentName -> ComponentClass

const server = serve({
    fetch: app.fetch,
    port: 3000,
});

new CossackNodeAdapter({
    server,
    componentRegistry,
});

You can generate a project pre-configured with this adapter using create-cossack-app.