GitHub Authentication

By default, new Coder deployments use a Coder-managed GitHub app to authenticate users. We provide it for convenience, allowing you to experiment with Coder without setting up your own GitHub OAuth app.

If you authenticate with it, you grant Coder server read access to your GitHub user email and other metadata listed during the authentication flow.

This access is necessary for the Coder server to complete the authentication process. To the best of our knowledge, Coder, the company, does not gain access to this data by administering the GitHub app.

Default Configuration

To use the default configuration:

1. Install the GitHub app in any GitHub organization that you want to use with Coder.

   The default GitHub app requires device flow to authenticate. This is enabled by default when using the default GitHub app. If you disable device flow using CODER_OAUTH2_GITHUB_DEVICE_FLOW=false, it will be ignored.

2. By default, only the admin user can sign up. To allow additional users to sign up with GitHub, add:

   CODER_OAUTH2_GITHUB_ALLOW_SIGNUPS=true

3. (Optional) If you want to limit sign-ups to specific GitHub organizations, set:

   CODER_OAUTH2_GITHUB_ALLOWED_ORGS="your-org"

Disable the Default GitHub App

You can disable the default GitHub app by configuring your own app or by adding the following environment variable to your Coder server configuration:

Step 1: Configure the OAuth application in GitHub

1. Register a GitHub OAuth app.

2. GitHub will ask you for the following Coder parameters:

   • Homepage URL: Set to your Coder deployment's CODER_ACCESS_URL (e.g. https://coder.domain.com)

   • User Authorization Callback URL: Set to https://coder.domain.com

     If you want to allow multiple Coder deployments hosted on subdomains, such as coder1.domain.com, coder2.domain.com, to authenticate with the same GitHub OAuth app, then you can set User Authorization Callback URL to the https://domain.com

3. Take note of the Client ID and Client Secret generated by GitHub. You will use these values in the next step.

4. Coder needs permission to access user email addresses.

   Find the Account Permissions settings for your app and select read-only for Email addresses.

Step 2: Configure Coder with the OAuth credentials

Coder server reads these settings from environment variables. Set them wherever your deployment manages environment variables. For example, use Helm values.yaml for Kubernetes or /etc/coder.d/coder.env for a system service.

Kubernetes (Helm): set the variables under coder.env in your values.yaml:

Then apply the change with helm upgrade:

System service: add the variables to /etc/coder.d/coder.env:

Then restart Coder with sudo service coder restart.

For GitHub Enterprise support, also set CODER_OAUTH2_GITHUB_ENTERPRISE_BASE_URL.

We recommend requiring and auditing MFA usage for all users in your GitHub organizations. This can be enforced from the organization settings page in the Authentication security sidebar tab.

Device Flow

Coder supports device flow for GitHub OAuth. This is enabled by default for the default GitHub app and cannot be disabled for that app.

For your own custom GitHub OAuth app, you can enable device flow by setting:

Device flow is optional for custom GitHub OAuth apps. We generally recommend using the standard OAuth flow instead, as it is more convenient for end users.