> ## Documentation Index
> Fetch the complete documentation index at: https://docs.parmanasystems.com/llms.txt
> Use this file to discover all available pages before exploring further.

# @parmana/execution-system

> The single interface every execution boundary implements: a no-op placeholder, an HTTP forwarder, and the real Execution Gateway all plug into the same seam.

<Info>**\[AVAILABLE]**. `packages/execution-system`. Note `DefaultExecutionSystem`'s real scope below, it is a placeholder, not a verified boundary.</Info>

## Purpose

Defines the one interface `RuntimeFactory.create()` needs to actually release an execution:
`ExecutionSystem`. `DefaultExecutionSystem`, `HttpExecutionSystem`, and
`@parmana/execution-gateway`'s `ExecutionGateway` are three different implementations of
this exact interface, interchangeable without touching `RuntimeEngine` or
`RuntimePipeline`.

## Install

```bash theme={null}
npm install @parmana/execution-system
```

## Key exports

| Export                        | Signature / Stability                                                                                                                                                                                                                                                                                       |
| ----------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `ExecutionSystem` (interface) | `{ execute(request: ExecutionRequest): Promise<ExecutionResult> }`. \[AVAILABLE]                                                                                                                                                                                                                            |
| `DefaultExecutionSystem`      | \[AVAILABLE], but a **placeholder**: `execute()` unconditionally returns `{ success: true, ... }`, echoing the request back. No policy re-check, no content-binding, no connector. Many tutorials (1-13) use this for simplicity to demonstrate the Runtime in isolation, it performs no real verification. |
| `HttpExecutionSystem`         | \[AVAILABLE]. `new HttpExecutionSystem({ baseUrl })`, `execute()` POSTs to `${baseUrl}/execute` and returns the parsed response.                                                                                                                                                                            |
| `ExecutionRequest`            | `{ businessTransactionId, action, target, parameters }`                                                                                                                                                                                                                                                     |
| `ExecutionTrustRecordBuilder` | \[AVAILABLE]. Assembles the final `ExecutionTrustRecord` from a transaction, decision, and execution result.                                                                                                                                                                                                |

<Warning>
  **`DefaultExecutionSystem` is not a smaller version of the gateway, it is a stand-in that
  does nothing.** If you see it in a tutorial's source, that tutorial is deliberately
  demonstrating the Runtime, Policy Engine, or trust record shape in isolation, not the
  verified end-to-end pipeline. The default `packages/api` server does **not** use
  `DefaultExecutionSystem`, it always constructs a real `ExecutionGateway`, see [The
  gateway](/concepts/the-gateway).
</Warning>

## Minimal example

```typescript theme={null}
import { RuntimeFactory } from "@parmana/runtime";
import { DefaultExecutionSystem } from "@parmana/execution-system";

const application = RuntimeFactory.create(
  transactionRepository,
  trustRecordRepository,
  policyRepository,
  new DefaultExecutionSystem(), // placeholder, always succeeds
);
```

For the real, verified boundary, see [@parmana/execution-gateway](/reference/execution-gateway).

## Next

<CardGroup cols={2}>
  <Card title="The gateway" icon="shield-check" href="/concepts/the-gateway">
    The real `ExecutionSystem` implementation the default server actually uses.
  </Card>

  <Card title="@parmana/runtime" icon="cog" href="/reference/runtime">
    Where this interface is consumed.
  </Card>
</CardGroup>