Create Your L1

Objectives

By the end of this exercise, you will be able to:

• Create an Avalanche L1 with a custom genesis configuration
• Enable Transaction AllowList and Contract Deployer AllowList at genesis
• Launch a BuilderHub hosted node and connect Core Wallet to your L1

Prerequisites

Before starting this exercise, ensure you have:

• BuilderHub account (create one if needed)
• Core Wallet installed and set to the correct network mode
• A funded wallet (testnet AVAX) to create the Subnet + Chain transactions - get tokens from the Console Faucet

Instructions

Step 1: Create the Subnet and Chain

Use Builder Console to create the Subnet and then create your chain.

Important: In the Precompiles section, enable both allowlist precompiles under Permissioning:

• Transaction AllowList
• Contract Deployer AllowList

Your connected wallet will be automatically assigned the Admin role for both.

Builder Console

Download Core Wallet

Checking requirements...

Save your Subnet ID, Blockchain ID, and Chain ID after creation. You'll need these later.

Step 2: Launch a BuilderHub Hosted Node

Start a managed node for your L1 (no Docker required for this step):

Builder Console

Download Core Wallet

Checking requirements...

Wait until the node is healthy and your chain is producing blocks.

Step 3: Convert Subnet to L1

Convert your Subnet into a sovereign L1:

This conversion is irreversible. Double-check you're converting the correct Subnet.

Builder Console

Download Core Wallet

Checking requirements...

Expected Output

You should have:

• A running L1 with a BuilderHub hosted node
• Core Wallet connected to your L1
• Both allowlist precompiles enabled from genesis

What's Next

In the next lessons, you'll:

1. Test the allowlist precompiles using the Builder Console
2. Intentionally remove yourself from the admin list to experience the restriction
3. Learn how to recover using network upgrades (which will require setting up a Docker validator)