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

# Change Data Capture

> Synchronize data between systems using CDC patterns

<Note>This page is a placeholder. Full content coming soon.</Note>

## Overview

Use FlowWarden as a **CDC pipeline** to propagate MongoDB changes to external systems — Elasticsearch, PostgreSQL, Kafka, or any downstream service.

```mermaid theme={null}
flowchart LR
    A[(MongoDB)] -->|Change Stream| B[FlowWarden]
    B --> C[Elasticsearch]
    B --> D[PostgreSQL]
    B --> E[Kafka]
```

## Why FlowWarden

* **Resume tokens** guarantee at-least-once delivery across restarts
* **DLQ** captures events that fail to sync, for manual replay
* **`@Filter`** lets you select only the collections and operations that matter