---
method: PUT
path: /api/system/config
auth: jwt+admin
area: system
---
<!-- source: internal/handlers/sidecar.go:396 SidecarHandler.UpdateSystemConfiguration -->

# Update System Configuration

Updates one or more system-wide configuration keys. Admin only. When
`base_url` is provided, derived keys (`opds_base_url`, `api_base_url`) are
updated automatically. `default_timezone` is validated as a timezone.

## Example request

```json example-request
{
  "base_url": "https://books.example.com",
  "default_timezone": "UTC"
}
```

## Example response

```json example-response
{
  "status": "success",
  "message": "System configuration updated"
}
```

## Fields

| Field | Type | Required | Notes |
| ----- | ---- | -------- | ----- |
| (any key) | string | No | Arbitrary config key/value pairs |

## Errors

| Status | Body | When |
| ------ | ---- | ---- |
| 400 | `{"error": "invalid request format"}` / `{"error": "invalid timezone"}` | malformed body or bad timezone |
| 401 | `{"error": "unauthorized"}` | no/invalid JWT |
| 403 | `{"error": "admin access required"}` | non-admin |
| 500 | `{"error": "failed to update config key: ..."}` / `{"error": "failed to update default timezone"}` / `{"error": "failed to update derived config key: ..."}` | unexpected server error |