Publishing to npm | Fern Documentation

Publish your public-facing Fern TypeScript SDK to the npm registry. After following the steps on this page, you’ll have a versioned package published on npm.

This page assumes that you have:

An initialized fern folder on your local machine. See Set up the fern folder.
A GitHub repository for your TypeScript SDK. See Set up your GitHub structure.
A TypeScript generator group in generators.yml. See TypeScript Quickstart.

Configure `generators.yml`

Configure `output` location

In the group for your TypeScript SDK, change the output location in from local-file-system (the default) to npm to indicate that Fern should publish your package directly to the npm registry:

1 groups: 
2   ts-sdk: # Group name for your TypeScript SDK
3     generators:
4       - name: fernapi/fern-typescript-sdk
5         version: 2.5.0
6         output:
7           location: npm

Add a unique package name

Your package name must be unique in the npm repository, otherwise publishing your SDK to npm will fail. Update your package name if you haven’t done so already:

1 groups: 
2   ts-sdk:
3     generators:
4       - name: fernapi/fern-typescript-sdk
5         version: 2.5.0
6         output:
7           location: npm
8           package-name: your-package-name

Configure `namespaceExport`

The namespaceExport option controls the name of the generated client. This is the name customers use to import your SDK (import { your-client-name } from 'your-package-name';).

1 groups: 
2   ts-sdk:
3     generators:
4       - name: fernapi/fern-typescript-sdk
5         version: 2.5.0
6         output:
7           location: npm
8           package-name: your-package-name
9         config:
10           namespaceExport: YourClientName # must be PascalCase

Add repository location

Add the path to your GitHub repository to generators.yml, if you haven’t already:

1 groups: 
2   ts-sdk:
3     generators:
4       - name: fernapi/fern-typescript-sdk
5         version: 2.5.0
6         output:
7           location: npm
8           package-name: your-package-name
9         config:
10            namespaceExport: YourClientName
11         github: 
12           repository: your-org/company-typescript

Generate an npm token

Log into npm

Log into npm or create a new account.

Navigate to Access Tokens

Click on your profile picture.
Select Edit Profile.
Select Access Tokens.

Generate Token

Click on Generate New Token, then choose the appropriate token type.

For more information on access tokens and which type to choose, see npm’s About access tokens documentation.

Option 1: Classic Token

Select Classic Token
Name your token and select Automation as the token type.
Click Generate Token.

Save your new token – it won’t be displayed after you leave the page.

Option 2: Granular Access Token

Select Granular Access Token.
Name your token.
Set an expiration.
Configure your token’s access to packages and scopes.
Configure your token’s access to organizations. In order to fill this out, you must have at least one organization already configured in npm. See Creating an organization for more information.
Optionally fill out additional permissions according to your organization’s requirements.
Click Generate Token.

Save your new token – it won’t be displayed after you leave the page.

Configure npm publication

Choose how you want to authenticate and publish your SDK to npm. You can use GitHub workflows for automated releases or publish directly via the CLI.

Release via a GitHub workflow (recommended)

Set up a release workflow via GitHub Actions so you can trigger new SDK releases directly from your repository.

Set up authentication

Open your Fern repository in GitHub. Click on the Settings tab in your repository. Then, under the Security section, open Secrets and variables > Actions.

You can also use the url https://github.com/<your-repo>/settings/secrets/actions.

Add secret for your npm Token

Select New repository secret.
Name your secret NPM_TOKEN.
Add the corresponding token you generated above.
Click Add secret.

Add secret for your Fern Token

Select New repository secret.
Name your secret FERN_TOKEN.
Add your Fern token. If you don’t already have one, generate one by running fern-token. By default, the fern_token is generated for the organization listed in fern.config.json.
Click Add secret.

Set up a new workflow

In your repo, navigate to Actions. Select New workflow, then Set up workflow yourself. Set up a workflow dispatch that is similar to this:

.github/workflows/publish.yml

1 name: Publish TypeScript SDK
2 
3 on:
4 workflow_dispatch:
5 	inputs:
6 	version:
7 		description: "The version of the TypeScript SDK that you would like to release"
8 		required: true
9 		type: string
10 
11 jobs:
12 release:
13 	runs-on: ubuntu-latest
14 	steps:
15 	- name: Checkout repo
16 		uses: actions/checkout@v4
17 
18 	- name: Install Fern CLI
19 		run: npm install -g fern-api
20 
21 	- name: Release TypeScript SDK
22 		env:
23 		FERN_TOKEN: ${{ secrets.FERN_TOKEN }}
24 		NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
25 		run: |
26 		fern generate --group ts-sdk --version ${{ inputs.version }} --log-level debug

Run your workflow

Navigate to the Actions tab, select the workflow you just created, and click Run workflow.

Once your workflow completes, log back into npm and navigate to Packages to see your new release.

Release via CLI and environment variables

Configure npm authentication token

Add token: ${NPM_TOKEN} to generators.yml to tell Fern to use the NPM_TOKEN environment variable for authentication when publishing to the npm registry.

1 groups: 
2   ts-sdk:
3     generators:
4       - name: fernapi/fern-typescript-sdk
5         version: 2.5.0
6         output:
7           location: npm
8           package-name: name-of-your-package
9           token: ${NPM_TOKEN}
10         config:
11           namespaceExport: YourClientName
12         github: 
13           repository: your-org/your-repository

When you regenerate your release, Fern will automatically create a workflow in your repository called .github/workflows/ci.yml that will automatically publish your release to npm. For an example, see Vapi’s npm publishing GitHub Action

Set npm environment variable

Set the NPM_TOKEN environment variable on your local machine:

$ export NPM_TOKEN=your-actual-npm-token

Regenerate your SDK

$ fern generate --group ts-sdk --version <version>

Local machine output will verify that the release is pushed to your repository and tagged with the version you specified. Log back into npm and navigate to Packages to see your new release.

Configure generators.yml

Configure output location