# Configuration

Configure your Supabase branches using configuration as code

This guide covers how to configure your Supabase branches, using the `config.toml` file. In one single file, you can configure all your branches, including branch settings and secrets.

## Branch configuration with remotes

When Branching is enabled, your `config.toml` settings automatically sync to all ephemeral branches through a one-to-one mapping between your Git and Supabase branches.

### Basic configuration

To update configuration for a Supabase branch, modify `config.toml` and push to git. The Supabase integration will detect the changes and apply them to the corresponding branch.

### Remote-specific configuration

For persistent branches that need specific settings, you can use the `[remotes]` block in your `config.toml`. Each remote configuration must reference an existing project ID.

Here's an example of configuring a separate seed script for a staging environment:

```toml
[remotes.staging]
project_id = "your-project-ref"

[remotes.staging.db.seed]
enabled = true
sql_paths = ["./seeds/staging.sql"]
```

Since the `project_id` field must reference an existing branch, you need to create the persistent branch before adding its configuration. Use the CLI to create a persistent branch first:

```bash
supabase --experimental branches create --persistent
# Do you want to create a branch named develop? [Y/n]
```

To retrieve the project ID for an existing branch, use the `branches list` command:

```bash
supabase --experimental branches list
```

This will display a table showing all your branches with their corresponding project ID.
Use the value from the `BRANCH PROJECT ID` column as your `project_id` in the remote configuration.

### Configuration merging

When merging a PR into a persistent branch, the Supabase integration:

1. Checks for configuration changes
2. Logs the changes
3. Applies them to the target remote

If no remote is declared or the project ID is incorrect, the configuration step is skipped.

### Available configuration options

All standard configuration options are available in the `[remotes]` block. This includes:

- Database settings
- API configurations
- Authentication settings
- Edge Functions configuration
- And more

You can use this to maintain different configurations for different environments while keeping them all in version control.

## Managing secrets for branches

For sensitive configuration like SMTP credentials or API keys, you can use the Supabase CLI to manage secrets for your branches. This is especially useful for custom SMTP setup or other services that require secure credentials.

To set secrets for a persistent branch:

```bash
# Set secrets from a .env file
supabase secrets set --env-file ./supabase/.env

# Or set individual secrets
supabase secrets set SMTP_HOST=smtp.example.com
supabase secrets set SMTP_USER=your-username
supabase secrets set SMTP_PASSWORD=your-password
```

These secrets will be available to your branch's services and can be used in your configuration. For example, in your `config.toml`:

```toml
[auth.smtp]
host = "env(SMTP_HOST)"
user = "env(SMTP_USER)"
password = "env(SMTP_PASSWORD)"
```

Secrets set for one branch are not automatically available in other branches. You'll need to set them separately for each branch that needs them.

### Using dotenvx for git-based workflow

For managing environment variables across different branches, you can use [dotenvx](https://dotenvx.com/) to securely manage your configurations. This approach is particularly useful for teams working with Git branches and preview deployments.

#### Environment file structure

Following the conventions used in the [example repository](https://github.com/supabase/supabase/blob/master/examples/slack-clone/nextjs-slack-clone-dotenvx/README.md), environments are configured using dotenv files in the `supabase` directory:

| File            | Environment | `.gitignore` it? | Encrypted |
| --------------- | ----------- | ---------------- | --------- |
| .env.keys       | All         | Yes              | No        |
| .env.local      | Local       | Yes              | No        |
| .env.production | Production  | No               | Yes       |
| .env.preview    | Branches    | No               | Yes       |
| .env            | Any         | Maybe            | Yes       |

#### Setting up encrypted secrets

1. Generate key pair and encrypt your secrets:

```bash
npx @dotenvx/dotenvx set SUPABASE_AUTH_EXTERNAL_GITHUB_SECRET "<your-secret>" -f supabase/.env.preview
```

This creates a new encryption key in `supabase/.env.preview` and a new decryption key in `supabase/.env.keys`.

2. Update project secrets:

```bash
npx supabase secrets set --env-file supabase/.env.keys
```

3. Choose your configuration approach in `config.toml`:

Option A: Use encrypted values directly:

```toml
[auth.external.github]
enabled = true
secret = "encrypted:<encrypted-value>"
```

Option B: Use environment variables:

```toml
[auth.external.github]
enabled = true
client_id = "env(SUPABASE_AUTH_EXTERNAL_GITHUB_CLIENT_ID)"
secret = "env(SUPABASE_AUTH_EXTERNAL_GITHUB_SECRET)"
```

The `encrypted:` syntax only works for designated "secret" fields in the configuration. Using encrypted values in other fields will not be automatically decrypted and may cause issues. For non-secret fields, use environment variables with the `env()` syntax instead.

The following fields support the `encrypted:` syntax:

**Studio**

- `studio.openai_api_key`

**Database**

- `db.root_key`
- `db.vault.*` (any key in the vault map)

**Auth - Core Keys**

- `auth.publishable_key`
- `auth.secret_key`
- `auth.jwt_secret`

**Auth - Email (SMTP)**

- `auth.email.smtp.pass`

**Auth - Captcha**

- `auth.captcha.secret`

**Auth - Hooks**

- `auth.hook.mfa_verification_attempt.secrets`
- `auth.hook.password_verification_attempt.secrets`
- `auth.hook.custom_access_token.secrets`
- `auth.hook.send_sms.secrets`
- `auth.hook.send_email.secrets`
- `auth.hook.before_user_created.secrets`

**Auth - SMS Providers**

- `auth.sms.twilio.auth_token`
- `auth.sms.twilio_verify.auth_token`
- `auth.sms.messagebird.access_key`
- `auth.sms.textlocal.api_key`
- `auth.sms.vonage.api_secret`

**Auth - External OAuth Providers**

- `auth.external.*.secret`

**Edge Runtime**

- `edge_runtime.secrets.*` (any key in the secrets map)

#### Using with preview branches

When you commit your `.env.preview` file with encrypted values, the branching executor will automatically retrieve and use these values when deploying your branch. This allows you to maintain different configurations for different branches while keeping sensitive information secure.

## Configuration examples

### Multi-environment setup

Here's an example of a complete multi-environment configuration:

```toml
# Default configuration for all branches
[api]
enabled = true
port = 54321
schemas = ["public", "storage", "graphql_public"]

[db]
port = 54322
pool_size = 10

# Staging-specific configuration
[remotes.staging]
project_id = "staging-project-ref"

[remotes.staging.api]
max_rows = 1000

[remotes.staging.db.seed]
sql_paths = ["./seeds/staging.sql"]

# Production-specific configuration
[remotes.production]
project_id = "prod-project-ref"

[remotes.production.api]
max_rows = 500

[remotes.production.db]
pool_size = 25
```

To retrieve the project ID for an existing branch, use the `branches list` command:

```bash
supabase --experimental branches list
```

This will display a table showing all your branches with their corresponding project ID.
Use the value from the `BRANCH PROJECT ID` column as your `project_id` in the remote configuration.

### Feature branch configuration

For feature branches that need specific settings:

```toml
[remotes.feature-oauth]
project_id = "feature-branch-ref"

[remotes.feature-oauth.auth.external.google]
enabled = true
client_id = "env(GOOGLE_CLIENT_ID)"
secret = "env(GOOGLE_CLIENT_SECRET)"
```

To retrieve the project ID for an existing branch, use the `branches list` command:

```bash
supabase --experimental branches list
```

This will display a table showing all your branches with their corresponding project ID.
Use the value from the `BRANCH PROJECT ID` column as your `project_id` in the remote configuration.

## Next steps

- Explore [branching integrations](/docs/guides/deployment/branching/integrations)
- Learn about [troubleshooting branches](/docs/guides/deployment/branching/troubleshooting)
- Review [branching pricing](/docs/guides/platform/manage-your-usage/branching#pricing)