# Runtime Environment Variables

These variables configure the RivetKit SDK inside your own process. Variables that
connect your backend to a Rivet control plane, select a runner pool, or spawn a
local engine live in [Environment Variables](/docs/environment-variables) in the
platform docs.

## Inspector

| Environment Variable | Description |
|---------------------|-------------|
| `RIVET_INSPECTOR_DISABLE` | Set to `1` to disable the inspector |

## Experimental

| Environment Variable | Description |
|---------------------|-------------|
| `RIVET_EXPERIMENTAL_OTEL` | Set to `1` to enable experimental OTel tracing in Rivet Actors |

## Storage

| Environment Variable | Description |
|---------------------|-------------|
| `RIVETKIT_RUNTIME` | Runtime binding to use for RivetKit core: `auto`, `native`, or `wasm`. Defaults to `auto`. |
| `RIVETKIT_STORAGE_PATH` | Overrides the default file-system storage path used by RivetKit when using the default driver. |

## Lifecycle

| Environment Variable | Description |
|---------------------|-------------|
| `RIVETKIT_RUNTIME_MODE` | Controls how `registry.start()` runs. Accepted values are `envoy` and `serverless`; any other explicit value errors. Defaults to `envoy`: opens a long-lived WebSocket to the control plane (Mode A). Set to `serverless` to bind an HTTP listener via `registry.listen()` (Mode B). |
| `RIVETKIT_PUBLIC_DIR` | Directory of static assets to serve alongside the framework routes when calling `registry.listen()`. Used as a fallback when `opts.publicDir` is not passed. On auto-listen via `registry.start()`, defaults to `/public` when this env var is unset. |
| `RIVET_PORT` | Port the listener binds when calling `registry.listen()` without an explicit `opts.port`. Must be an integer between 1 and 65535. Defaults to `3000`. |

## Logging

| Environment Variable | Description |
|---------------------|-------------|
| `RIVET_LOG_LEVEL` | Log level: `trace`, `debug`, `info`, `warn`, `error`, `fatal`, `silent` |
| `RIVET_LOG_TARGET` | Set to `1` to include log target |
| `RIVET_LOG_TIMESTAMP` | Set to `1` to include timestamps |
| `RIVET_LOG_MESSAGE` | Set to `1` to include message formatting |
| `RIVET_LOG_ERROR_STACK` | Set to `1` to include error stack traces |
| `RIVET_LOG_HEADERS` | Set to `1` to log request headers |