> For the complete documentation index, see [llms.txt](https://docs.substreams.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.substreams.dev/how-to-guides/sinks/hosted-sinks.md).

# Hosted Sinks

**Hosted Sinks** is a managed service on [The Graph Market](https://thegraph.market) that runs your Substreams sink for you. Instead of provisioning servers, managing deployments, or operating sink processes yourself, you configure a sink in the portal and StreamingFast handles the infrastructure.

A hosted sink continuously reads data from your Substreams package and writes it to your own Postgres or ClickHouse database.

{% hint style="info" %}
Hosted Sinks is available to organizations on The Graph Market. Your database must be publicly reachable from StreamingFast's infrastructure.
{% endhint %}

## Requirements

Before creating a sink, you need:

* An account on [The Graph Market](https://thegraph.market) with an active organization.
* A Substreams package (`.spkg`) that outputs data using a `db_out` module or relational mappings. See [Substreams:SQL](/how-to-guides/sinks/sql.md) for how to build one.
* A running Postgres (default port `5432`) or ClickHouse (default port `9000`) database that is network-accessible from the internet.
* Your database schema already applied, or a schema that your Substreams package will create automatically. See [Sink Config](/reference-material/sql/sql/sink-config.md).

## Creating a Sink

Navigate to [**Sinks**](https://thegraph.market/sinks) in the sidebar and click **New Sink**.

![](/files/RoTpope08nr7knqPBs4f)

### 1. Basics

Enter a **Sink name**. This is a human-readable label for the deployment (e.g., `mainnet-erc20-transfers`).

### 2. Substreams Package

Choose how you want to supply the `.spkg`:

| Source             | When to use                                                                                                                   |
| ------------------ | ----------------------------------------------------------------------------------------------------------------------------- |
| **URL**            | The package is hosted at a public URL (e.g., GitHub releases, IPFS).                                                          |
| **Substreams.dev** | The package is published on [the Substreams Registry](https://substreams.dev). Enter its ID (e.g., `ethereum_common@v0.3.3`). |

### 3. Output

Choose **Postgres** or **ClickHouse** and fill in the connection details.

**Postgres fields:**

| Field    | Description                                                 |
| -------- | ----------------------------------------------------------- |
| Host     | Database hostname or IP address.                            |
| Port     | Default `5432`.                                             |
| Database | Database name.                                              |
| Schema   | Target schema. Default `public`.                            |
| User     | Database user with write access.                            |
| Password | Password for the user.                                      |
| SSL Mode | One of `disable`, `require`, `verify-ca`, or `verify-full`. |

**ClickHouse fields:**

| Field        | Description                        |
| ------------ | ---------------------------------- |
| Host         | ClickHouse hostname or IP address. |
| Port         | Default `9000` (native protocol).  |
| Database     | Database name. Default `default`.  |
| User         | ClickHouse user.                   |
| Password     | Password for the user.             |
| Secure (TLS) | Enable TLS for the connection.     |

{% hint style="warning" %}
Credentials are stored securely and used only to connect the sink process to your database. Use a dedicated database user with write access restricted to the target schema.
{% endhint %}

### 4. Execution

| Field         | Description                                                                                 |
| ------------- | ------------------------------------------------------------------------------------------- |
| Start block   | Block number to start processing from. Use `0` to start from genesis.                       |
| Stop block    | Block number to stop at. Use `0` to follow the chain head indefinitely.                     |
| Output module | The name of the Substreams module whose output is written to the database (e.g., `db_out`). |

**Advanced options** (optional):

| Field      | Description                                             |
| ---------- | ------------------------------------------------------- |
| Filters    | A filter expression passed to the Substreams execution. |
| Parameters | Module parameters passed at execution time.             |

### 5. Deploy

Click **Deploy sink**. The sink enters the `Deploying` state while the infrastructure provisions. Once pods are ready it transitions to `Deployed` and begins indexing.

## Next Steps

* [Monitor and manage your sink](/how-to-guides/sinks/hosted-sinks/manage-your-sink.md) — check status, view logs, edit config, stop, or delete.


---

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