---
title: "Integrate into an Existing Worker"
description: "Mount teenybase inside an existing Cloudflare Worker (usually a Hono app): init, wiring, D1 and R2 bindings, sub-path mounting and deploy."
url: https://teenybase.com/docs/reference/integrate-existing-worker
last_updated: 2026-10-26
---

> Documentation index: https://teenybase.com/llms.txt lists every teenybase docs page with a link to its Markdown version. All docs in one file: https://teenybase.com/llms-full.txt

# Integrate into an Existing Worker

Use this when you have an existing Cloudflare Worker (typically a Hono app) and want to mount teenybase into it instead of running a separate backend folder. This is the advanced path. For most projects, [creating a separate backend folder](https://teenybase.com/docs/getting-started/existing-project) is simpler.

## 1. Install

```bash
npm install teenybase hono
npm install -D wrangler @cloudflare/workers-types typescript
```

## 2. Scaffold with `npx teenybase init`

```bash
npx teenybase init -t with-auth -y
```

`npx teenybase init` creates the missing teenybase files without touching your existing files:

- `teenybase.ts`
- `src/index.ts` (only if it doesn't exist)
- `wrangler.jsonc`
- `worker-configuration.d.ts`
- `.dev.vars`
- `migrations/`

It also patches `tsconfig.json` so `virtual:teenybase` resolves correctly.

`npx teenybase init` does not modify an existing `package.json`, which is why you install dependencies yourself in step 1.

## 3. Wire into your existing worker

If `src/index.ts` already exists, `npx teenybase init` will not replace it. You need to add teenybase yourself.

Pass your existing Hono app as the second argument to `teenyHono()`:

```ts
import { Hono } from 'hono'
import {$Database, $Env, OpenApiExtension, PocketUIExtension, D1Adapter, teenyHono} from 'teenybase/worker'
import config from 'virtual:teenybase'

type Env = $Env & {Bindings: CloudflareBindings}

const app = new Hono<Env>()

// your existing routes
app.get('/healthz', (c) => c.json({ ok: true }))
app.get('/hello', (c) => c.text('Hello from my existing app'))

// add teenybase routes to your app
teenyHono<Env>(async (c) => {
  const db = new $Database(c, config, new D1Adapter(c.env.PRIMARY_DB))
  db.extensions.push(new OpenApiExtension(db, true))
  db.extensions.push(new PocketUIExtension(db))
  return db
}, app)

export default app
```

Your routes and teenybase's `/api/v1/*` routes coexist on the same app.

## 4. Add D1 binding

Add the D1 database binding to `wrangler.jsonc`:

```jsonc
{
  "d1_databases": [
    {
      "binding": "PRIMARY_DB",
      "database_name": "<your-database-name>",
      "database_id": "<your-database-id>",
      "migrations_dir": "migrations"
    }
  ]
}
```

Regenerate types:

```bash
npx wrangler types --env-interface CloudflareBindings
```

## 5. Run locally

```bash
npx teenybase deploy --local
npx teenybase dev
```

## Mounting under a sub-path

If you want teenybase at a custom prefix (e.g. `/backend/api/v1/...`), use Hono's `app.route()`:

```ts
const teenyApp = teenyHono<Env>(async (c) => {
  return new $Database(c, config, new D1Adapter(c.env.PRIMARY_DB))
})

const app = new Hono<Env>()
app.get('/', (c) => c.text('Home'))
app.route('/backend', teenyApp)  // teenybase at /backend/api/v1/...

export default app
```

## File uploads (R2)

Add the R2 bucket binding to `wrangler.jsonc`:

```jsonc
{
  "r2_buckets": [
    {
      "binding": "R2_BUCKET",
      "bucket_name": "my-app-files"
    }
  ]
}
```

Regenerate types:

```bash
npx wrangler types --env-interface CloudflareBindings
```

Pass the bucket as the fourth argument to `$Database`:

```ts
const db = new $Database(c, config, new D1Adapter(c.env.PRIMARY_DB), c.env.R2_BUCKET)
```

## Deploy

```bash
cp .dev.vars .prod.vars
```

```bash
npx wrangler login          # one-time
npx teenybase deploy --remote --yes
```

The deploy prints the worker URL and saves it as `apiRoute` in `infra.jsonc`.

## Where code should live

- `teenybase.ts` = schema, rules, auth, actions, email config
- `src/index.ts` = worker wiring, extensions, custom Hono routes, R2 binding

Do not put app routes into `teenybase.ts`.