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

# React Server Components

# React Server Components

***

## Core · React Server Components

> **Core principle** — Treat RSC as a boundary to evaluate deliberately, not a label to apply to every component.

A clear decision about server/client ownership, serialization, caching, and maturity risk.

### Key concepts

<Columns cols={3}>
  <Card title="Server code" icon="sparkles">
    No browser APIs
  </Card>

  <Card title="Client code" icon="shield-check">
    Interactive behavior
  </Card>

  <Card title="Payload" icon="gauge-high">
    Serializable data
  </Card>
</Columns>

### Boundary model

```mermaid placement="top-right" theme={null}
flowchart LR
    server[Server component] --> payload[Serializable payload]
    payload --> client[Client component]
    client --> action[Browser interaction]
    action --> server
```

### Ownership matrix

| Concern     | Jeston/application boundary | Review signal                  |
| ----------- | --------------------------- | ------------------------------ |
| Server code | No browser APIs             | Runs in the server runtime.    |
| Client code | Interactive behavior        | Ships to the browser.          |
| Payload     | Serializable data           | Defines the crossing contract. |

### Engineering considerations

RSC changes where code executes and how data crosses the boundary; it affects tooling, debugging, and deployment assumptions.

> **Design constraint**
>
> A rendering model is mature when its boundaries are predictable under failure, not only when its demo is fast.

### Implementation notes

| Engineering move           | Guidance                                                           |
| -------------------------- | ------------------------------------------------------------------ |
| **Classify execution**     | Mark data access, secrets, browser APIs, and event handlers.       |
| **Define serialization**   | Keep the crossing payload explicit and stable.                     |
| **Choose cache ownership** | Decide whether freshness belongs to request, server, or client.    |
| **Record maturity**        | Separate supported behavior from an experimental or roadmap track. |

### Decision lens

| Mode                | Practical emphasis                                          |
| ------------------- | ----------------------------------------------------------- |
| **Server boundary** | Use for secure data access and non-interactive composition. |
| **Client boundary** | Use for browser state, events, and device capabilities.     |
| **Hybrid**          | Keep the crossing narrow and inspect the payload.           |

## Related topics

<Columns cols={3}>
  * [server · **Compare SSR behavior**](/jeston/jeston/core/react-ssr) — Read the focused guide for this boundary.
  * [diagram-project · **Review runtime layers**](/jeston/jeston/core/architecture) — Read the focused guide for this boundary.
  * [scale-balanced · **Check support envelope**](/jeston/jeston/reference/compatibility) — Read the focused guide for this boundary.
</Columns>

## References

[1]: https://github.com/jeffersoncampos12p-dev/jeston "Jeston source repository"

[2]: https://www.npmjs.com/package/@kvantjs/jeston "Jeston package on npm"

[3]: https://nodejs.org/api/http.html "Node.js HTTP API"

[4]: https://developer.mozilla.org/en-US/docs/Web/API/AbortSignal "AbortSignal Web API"

[5]: https://react.dev/reference/react-dom/server "React server rendering APIs"

[6]: https://www.typescriptlang.org/docs/handbook/intro.html "TypeScript handbook"