# Networking and regions

Configure sandbox egress and deployment region.

Runtime configuration controls where the sandbox runs and which external hosts it can reach.

## Region

Pin a deployment to a supported region:

```yaml
runtimeConfig:
  sandboxRegion: eu
```

Supported values are:

```text
us
eu
```

When omitted, the deployment inherits the workspace default captured when the deployment is created.

The run Details view shows the resulting region and platform-selected machine specification.

## Restricted egress

```yaml
runtimeConfig:
  egressPolicyMode: restricted
  egressAllowlist:
    - api.openai.com
    - '*.githubusercontent.com'
```

Allowlist values:

* contain a hostname or supported wildcard;
* do not include `https://`;
* do not include a path;
* do not include a port.

## Full-open egress

```yaml
runtimeConfig:
  egressPolicyMode: full-open
```

Use full-open egress only when the integration cannot operate with a bounded host list. Restricted mode is easier to review and safer for sandbox-exposed credentials.

## Managed proxy behavior

Managed sandbox HTTPS traffic uses the platform proxy and certificate authority. Salambo separately manages the service destinations required to operate the run; builders do not add or edit those destinations.

Customer allowlists describe customer-required destinations. They do not replace platform networking policy.

For OAuth integrations, `runtimeConfig.credentialExchanges` can bind an exact token endpoint to named Salambo secrets and approved API hosts. The proxy replaces sealed request fields and returns a sealed short-lived access token. Sandbox code never receives the source refresh token, client secret, or plaintext access token. See the [salambo.yaml reference](/docs/reference/salambo-yaml#sealed-credential-exchanges) for the complete contract.

See [sandbox security architecture](/docs/architecture/sandbox-security) for TLS inspection, sealed-secret substitution, and fail-closed destination checks.