- `cargo run -- --help` should display this help screen:
```
Backup service
Usage: backup [OPTIONS]
Options:
--port <LISTENING_PORT>
gRPC server listening port [default: 50051]
--sandbox
Run the service in sandbox [env: COMM_SERVICES_SANDBOX=]
--localstack-url <LOCALSTACK_URL>
AWS Localstack service URL, applicable in sandbox mode [default: http://localstack:4566]
--blob-service-url <BLOB_SERVICE_URL>
Blob service URL [default: http://blob-server:50053]
-h, --help
Print help information
-V, --version
Print version information
```
- `cargo run` without args should start service on default port `50051`
- `cargo run -- --port 50052` should start service on port `50052` (or any other specified unless already used)