# `NervesGateSDK.Backend`

Implemented by device firmware and the host simulator.

`call/2` runs in the caller's process. Implementations must preserve caller
ownership when forwarding subscriptions or RS485 claims to another process.
Backends return SDK-owned structs and never expose private domain state.

# `operation`

```elixir
@type operation() ::
  :system_info
  | :network_interfaces
  | :events_subscribe
  | :events_unsubscribe
  | :storage_status
  | :storage_data_dir
  | :can_interfaces
  | :can_send
  | :can_subscribe
  | :can_unsubscribe
  | :rs485_ports
  | :rs485_claim
  | :rs485_write
  | :rs485_release
  | :equipment_list
```

# `call`

```elixir
@callback call(operation(), list()) :: :ok | {:ok, term()} | {:error, term()}
```

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*Consult [api-reference.md](api-reference.md) for complete listing*