---
title: Code Generation
description: Extend your Turborepo with new apps, and packages. Create new empty workspaces, copy existing workspaces, add workspaces from remote sources (just like `create-turbo`!) or run custom generators defined using Plop configurations.
---

import { Callout } from "../../../../../components/Callout";

# Code Generation

Splitting your monorepo into individual workspaces is a great way to organize your code, speed up tasks, and improve the local development
experience. With Turborepo's code generation, it's easy to generate new source code for packages, modules,
and even individual UI components in a structured way that integrates with the rest of your repository.

## Add an Empty Workspace

Add a new, empty app or package to your monorepo.

```sh
turbo gen workspace
```

View all available [options](/repo/docs/reference/command-line-reference/gen#workspace) for `gen workspace`.

![Extend your Turborepo by adding a new package or application](/images/docs/turborepo-generators-empty.png)

## Copy an Existing Workspace

You can use an existing workspace as a template for your new app or package. This works for both workspaces within your existing monorepo,
and remote workspaces from other repositories (specified via GitHub URL).

### Examples

Create a new workspace in your monorepo by copying from an existing workspace in your repo.

```sh
turbo gen workspace --copy
```

Create a new workspace in your monorepo by copying from a remote workspace.

```sh
turbo gen workspace --copy https://github.com/vercel/turbo/tree/main/examples/with-tailwind/packages/tailwind-config
```

<Callout>
  **Note**: When adding from a remote source, Turborepo is unable to verify that your repo has all of the required dependencies, and is using the correct package manager. In this case, some manual modifications may be required to get the new workspace working as expected within your repository.

</Callout>

View all available [options](/repo/docs/reference/command-line-reference/gen#workspace) for `gen workspace --copy`.

![Extend your Turborepo by copying an existing package or application](/images/docs/turborepo-generators-copy.png)

## Custom Generators

If a built-in generator does not fit your needs, you can create your own custom generator using [Plop](https://plopjs.com/) configurations.
Turborepo will automatically detect any generator configurations within your repo, and make them available to run from the command line.

<Callout type="info">
  **Note**: While Turborepo Generators are built on top of Plop, they _do not_ require `plop` to be installed as a dependency in your repo.
</Callout>

While Turborepo understands all Plop configuration options and features, it provides a few additional features to improve the experience of writing
generators within a repo configured with Turborepo.

1. Generators are automatically discovered, loaded, and organized per workspace (no need to manually `load` them within a single configuration file)
2. Generators are automatically run from the root of the workspace where they are defined
3. Generators can be invoked from anywhere within your repo (or outside out it via the [`--root`](/repo/docs/reference/command-line-reference/gen#--root) flag)
4. Typescript generators are supported with zero configuration
5. `plop` is not required to be installed as a depenendency of your repo

<Callout>
  **Note:** ESM dependencies are not currently supported within custom generators
</Callout>

### Getting Started

To build and run a custom generator, run the following command from anywhere within your monorepo using Turborepo.

```sh
turbo gen
```

You'll be prompted to select an existing generator or to create one if you don't have any yet. You can also create your configuration
manually at `turbo/generators/config.ts` (or `config.js`) at the root of your repo - or within _any_ workspace.

<Callout type="info">
  **Note**: If you are using Typescript, you will need to install the [`@turbo/gen`](https://github.com/vercel/turbo/tree/main/packages/turbo-gen) package as a `devDependency` to access the required TS types.
</Callout>

For example, the following illustrates a monorepo with three generator configurations:

```
- root
- apps/web
- packages/ui
```

```bash
├── package.json
├── turbo.json
├── README.md
├── apps
│   └── web
│       ├── package.json
│       └── turbo
│           └── generators
│               ├── config.ts
│               └── templates
├── packages
│   └── ui
│       ├── package.json
│       └── turbo
│           └── generators
│               ├── config.ts
│               └── templates
├── turbo
│   └── generators
│       ├── config.ts
│       └── templates
├── pnpm-lock.yaml
└── pnpm-workspace.yaml
```

Generators created within workspaces are automatically run from the workspace root, **not** the repo root, nor the location of the generator configuration.

This makes your generators more simple to write. Creating a file at `[workspace-root]` only needs to be specified as `<file>` rather than `../../<file>`.

Learn more about [creating custom generators using Plop](https://plopjs.com/documentation/#creating-a-generator).

### Writing Generators

A generator configuration file is a function that returns a [Plop](https://plopjs.com/) configuration object. The configuration object is
used to define the generator's prompts, and actions.

In its simplest form, a generator configuration file looks like:

```ts filename="turbo/generators/config.ts"
import type { PlopTypes } from "@turbo/gen";

export default function generator(plop: PlopTypes.NodePlopAPI): void {
  // create a generator
  plop.setGenerator("Generator name", {
    description: "Generator description",
    // gather information from the user
    prompts: [
      ...
    ],
    // perform actions based on the prompts
    actions: [
      ...
    ],
  });
}
```

#### Prompts

Prompts are written using [Plop prompts](https://plopjs.com/documentation/#using-prompts) and are used to gather information from the user.

#### Actions

Actions can use [built-in Plop actions](https://plopjs.com/documentation/#built-in-actions), or [custom action functions](https://plopjs.com/documentation/#functionsignature-custom-action) that you define yourself:

```ts filename="turbo/generators/config.ts"
import type { PlopTypes } from "@turbo/gen";

const customAction: PlopTypes.CustomActionFunction = async (answers) => {
  // fetch data from a remote API
  const results = await fetchRemoteData();
  // add the response to the answers, making this data available to actions
  answers.results = results;
  // return a status string
  return 'Finished data fetching!';
}

export default function generator(plop: PlopTypes.NodePlopAPI): void {
  // create a generator
  plop.setGenerator("Generator name", {
    description: "Generator description",
    prompts: [
      ...
    ],
    actions: [
      customAction
      {/* actions now have access to `answers.results` */}
      ...
    ],
  });
}
```

### Running Generators

Once you have created your generator configuration file, you can skip the selection prompt and directly run a specified generator with:

```sh
turbo gen [generator-name]
```

Arguments can also be passed directly to the generator prompts using `--args`

```sh
turbo gen [generator-name] --args answer1 answer2 ...
```

See [bypassing prompts](https://plopjs.com/documentation/#bypassing-prompts) in the Plop documentation for more information.

View all available [options](/repo/docs/reference/command-line-reference#run-generator-name) for `gen`.

## Examples

The [vercel/turbo](https://github.com/vercel/turbo) monorepo contains several custom Turborepo generators that are used for our own development.

- [Create a new blog post](https://github.com/vercel/turbo/blob/main/docs/turbo/generators/config.ts) - Creates a new release [blog post](/blog) with
  live stats fetched from the NPM and Github API's.
- [Create a new code transform](https://github.com/vercel/turbo/blob/main/packages/turbo-codemod/turbo/generators/config.ts) - Creates a new code transform
  for [`@turbo/codemod`](https://github.com/vercel/turbo/tree/main/packages/turbo-codemod) complete with all boilerplate and tests.

Turborepo Examples

- [examples/basic](https://github.com/vercel/turbo/blob/main/examples/basic/packages/ui/turbo/generators/config.ts)
