# on World Chain

In this tutorial, you'll learn how to initialize a World Chain-based Substreams project using the Substreams CLI (`substreams init` command).

{% hint style="info" %}
The CLI installation is supported only on Linux and macOS. If you're using Windows, consider using the [DevContainer environment](/reference-material/development-tools/devcontainer-ref.md), which launches a Linux-based virtual environment.
{% endhint %}

### Step 1: Initialize Your World Chain Substreams Project

1. [Install the Substreams CLI](/how-to-guides/installing-the-cli.md)
2. Running `substreams init` will give you the option to choose between two EVM project options. Select the one that best fits your requirements:
   * **evm-hello-world**: Creates a simple Substreams that outputs the events of a smart contract. For World Chain, this will typically use a common smart contract address available on the network.
   * **evm-events-calls**: Creates a Substreams that extracts and decodes EVM events and calls using the cached [EVM Foundational Module](https://substreams.dev/streamingfast/ethereum-common/v0.3.0), filtered by one or more smart contract addresses. Contract ABIs are retrieved from Etherscan-compatible block explorers. If an ABI isn't available, you'll need to provide it yourself.

### Step 2: Configure Your World Chain Endpoint

When running your Substreams commands, use the World Chain endpoint:

```bash
substreams run -e mainnet.worldchain.streamingfast.io:443 substreams.yaml [module_name] --start-block [block_number]
```

### Step 3: Visualize the Data

1. Run `substreams auth` to create your [account](https://thegraph.market/) and generate an authentication token (JWT), then pass this token back as input.
2. Run `substreams build` to compile the project.
3. Run `substreams gui -e mainnet.worldchain.streamingfast.io:443` to visualize and iterate on your extracted data.

### Step 3.5: (Optionally) Transform the Data

1. Open the `src/lib.rs` file that has been generated.
2. Modify the transformations made to the data as needed. Every time you modify the code, you will have to recompile the project with `substreams build`.

### Step 4: Load the Data

To make your Substreams queryable (as opposed to [direct streaming](/how-to-guides/sinks/stream.md)), you can automatically send the data to a SQL database by using the [SQL sink](/how-to-guides/sinks/sql.md) or through [PubSub](/how-to-guides/sinks/pubsub.md).

### World Chain Specifics

World Chain is an EVM-compatible blockchain, which means:

* It uses the same [`sf.ethereum.type.v2.Block`](https://github.com/streamingfast/firehose-ethereum/blob/develop/proto/sf/ethereum/type/v2/type.proto) protobuf model as other EVM chains
* All EVM-based Substreams modules and patterns work seamlessly
* You can leverage existing EVM foundational modules and libraries
* Smart contract interactions follow standard EVM patterns

### Additional Resources

You may find these additional resources helpful for developing your first World Chain application.

#### Dev Container Reference

The [Dev Container Reference](/reference-material/development-tools/devcontainer-ref.md) helps you navigate the container and its common errors.

#### CLI Reference

The [CLI reference](/reference-material/command-line-interface.md) lets you explore all the tools available in the Substreams CLI.

#### Substreams Components Reference

The [Components Reference](/reference-material/manifest-and-components/packages.md) dives deeper into navigating the `substreams.yaml`.

#### EVM Development Guide

Since World Chain is EVM-compatible, you can also refer to the general [EVM development guide](/how-to-guides/develop-your-own-substreams/on-evm/exploring-ethereum.md) for more advanced patterns and techniques.


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```
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