Introduction

Codexa Core targets Deno as its primary runtime, but keeps its HTTP layer runtime neutral by design. Every request handler is a plain function that accepts a standard Request and returns a standard Response. This is what lets the same application run on Bun and Cloudflare Workers unchanged, and on Node.js with a small Fetch API adapter.

Instead of one large bundle, the framework ships as small, focused packages. A project imports only the parts it needs:

• An HTTP layer built on a radix tree router
• An OpenAPI 3.1 generator
• A typed frontend SDK generator powered by OpenAPI route metadata
• Environment and database configuration
• An event bus
• A key value store
• A cache
• A storage manager for local disk, S3, Cloudinary, and ImageKit
• A command line tool, installed and used separately, for pulling plugin source from a Git repository

Plugin first

Every capability in Codexa Core, from a single health check route to a full authentication system, is built as a plugin. A plugin owns its routes, middleware, version header, and lifecycle hooks. It exposes services to other plugins only when it explicitly chooses to.

import { createApp, definePlugin } from '@codexa/core/http';

const healthPlugin = definePlugin({
  name: 'health',
  setup(scope) {
    scope.route({
      method: 'GET',
      path: '/health',
      handler: (ctx) => ctx.json({ ok: true }),
      options: { name: 'health.check', tags: ['public', 'health'] },
    });
  },
});

const app = createApp('api').install(healthPlugin);

Deno.serve(app.dispatch);

Another plugin can only reach health if it lists health in dependsOn, and only through whatever health exposes with exposeService. This ownership model keeps a large application predictable as more plugins are added.

Runs wherever the Fetch API runs

This portability comes from app.dispatch, the single function every runtime hands a request to. Pass it directly to whichever server or platform you deploy to.

Deno.serve(app.dispatch);

JSR's own compatibility check confirms this for Node.js, Deno, Bun, and browsers. Cloudflare Workers support is demonstrated in the framework's source, though JSR has not yet run its automated check for that platform.

Subpath imports

Each capability below is its own subpath, so a project that only needs the HTTP layer never loads the MongoDB driver or the Redis client.

Where the code lives

Codexa Core is published on JSR as @codexa/core, currently at version 1.0.5 with a JSR score of 100 percent. The source lives on GitHub at Codexa-by-HQ/codexa-core, under the MIT license.