> ## Documentation Index
> Fetch the complete documentation index at: https://docs.appliedaifoundation.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Environment variables

> Every env var the app reads, what it does, and what it defaults to.

The app reads its config exclusively from environment variables. Set them in `.env.local` for local dev or in the Vercel project settings for deployment.

## Required

### Database

| Var                                  | Description                                                 |
| ------------------------------------ | ----------------------------------------------------------- |
| `POSTGRES_USER`                      | DB user                                                     |
| `POSTGRES_PASSWORD`                  | DB password                                                 |
| `POSTGRES_DB`                        | DB name                                                     |
| `CLOUD_SQL_INSTANCE_CONNECTION_NAME` | GCP Cloud SQL instance ID — `<project>:<region>:<instance>` |
| `GOOGLE_SERVICE_ACCOUNT_BASE64`      | Service account JSON, base64-encoded                        |

The platform expects to authenticate through the Cloud SQL Connector. Direct DB password connections are not supported.

## Optional (with defaults)

### Table names

The platform supports running against differently-named tables — useful for multi-tenant or staging setups.

| Var                 | Default                   | Description                              |
| ------------------- | ------------------------- | ---------------------------------------- |
| `TABLE_VESSELS`     | `common_vessel_details`   | Vessel registry table                    |
| `TABLE_CONSUMPTION` | `common_consumption_log`  | Consumption logs table                   |
| `TABLE_PARTICULARS` | `vessel_particulars_data` | Vessel particulars (DWT, GT, flag, etc.) |

### Pricing

| Var                 | Default | Description                                                                                        |
| ------------------- | ------- | -------------------------------------------------------------------------------------------------- |
| `DEFAULT_EUA_PRICE` | `75`    | EU Allowance price in EUR. Used in EU ETS cost projections across all pages and the EU ETS report. |

## Example `.env.local`

```bash theme={"system"}
# Database (Google Cloud SQL) — replace placeholders with your own values
POSTGRES_USER=<your-db-user>
POSTGRES_PASSWORD=<your-db-password>
POSTGRES_DB=<your-db-name>
CLOUD_SQL_INSTANCE_CONNECTION_NAME=<gcp-project>:<region>:<instance-name>
GOOGLE_SERVICE_ACCOUNT_BASE64=<base64-encoded service account JSON>

# Optional overrides
DEFAULT_EUA_PRICE=85
```

<Warning>
  Never commit real values for these variables. Use `.env.local` (git-ignored) for local development and your hosting provider's secret manager for production. Rotate the service account JSON if it is ever exposed.
</Warning>

## Generating the service account base64

```bash theme={"system"}
base64 -i path/to/service-account.json | tr -d '\n' | pbcopy
```

Paste the result into `.env.local`. The platform decodes it at startup and uses it to authenticate with Cloud SQL.

## How vars are loaded

* **Local**: Next.js auto-loads `.env`, `.env.local`, `.env.development.local` from the repo root
* **Vercel**: Set them in Project → Settings → Environment Variables. Use the Vercel CLI's `vercel env pull` to mirror them locally.

## Security notes

* The service account JSON is decoded into `/tmp` at startup, then deleted after the connector reads it. The file mode is `0o600`.
* No env var is exposed to the client — every secret-bearing read happens server-side.
* CSP headers in `next.config.ts` further restrict where the app can be framed from.