# Deploy Smart Contracts with Remix

In this tutorial, we’ll walk you through **creating and deploying a basic ERC-20 token dApp** on the HeLa testnet using **Remix IDE,** which is an open source web and desktop application that provides a fast development cycle with intuitive GUIs and a rich set of plugins. 

### **Prerequisites**

Before we start, let’s make sure you’ve got the right setup:

1. **Browser**: Chrome, Brave, or Firefox (latest versions work best).
2. **Wallet** : 

   [MetaMask installed.](https://docs.helalabs.com/wallet/metamask)

   * Add the HeLa [testnet RPC](https://docs.helalabs.com/network-endpoints-and-explorer) (details will be shared by the chain team).
   * Fund your wallet with testnet tokens ([faucet link](https://docs.helalabs.com/network-endpoints-and-explorer/images-and-media)).
3. **Remix IDE**: No install required. Just open Remix in your browser. \
   Visit [https://remix.ethereum.org](https://remix.ethereum.org/)

### **Step 1: Create ERC-20 Token Contract**

1. In the file explorer, create a new file under the `contracts` folder named `MyToken.sol`
2. Copy and paste the following ERC-20 token contract code:

```jsx
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";

/// @title MyToken - A basic ERC20 Token on HeLa Chain
/// @custom:dev-run-script ./scripts/deploy.js

contract MyToken is ERC20 {
    constructor(uint256 initialSupply) ERC20("MyFirstHeLaToken", "HLT") {
       _mint(msg.sender, initialSupply * 10 ** decimals());
    }
}

```

**Customizing Your Token**

You can customize your token by changing:

* `"MyFirstHelaToken"` - The token name
* `"HLT"` - The token symbol (appears in MetaMask, max 5 characters)
* `5000` - The initial token supply minted to your wallet \</aside>

### Step 2: Adding a Deploy Script

Remix uses **NatSpec annotations** to link contracts with scripts.

1. In Remix’s File Explorer, create a folder: `scripts/`.
2. Create `deploy.js` inside it.
3. Paste this code:

```jsx
// scripts/deploy.js
async function main() {
    // Get the signer (the deployer wallet from Remix environment)
    const [deployer] = await ethers.getSigners();

    console.log("Deploying contracts with account:", deployer.address);

    // Compile + get contract factory
    const Token = await ethers.getContractFactory("MyToken");

    // Deploy contract
    const token = await Token.deploy();
    await token.deployed();

    console.log("MyToken deployed to:", token.address);
}

// Run the script with error handling
main()
    .then(() => process.exit(0))
    .catch((error) => {
        console.error(error);
        process.exit(1);
    });
```

### **Step 3: Compile the Contract**

Before deploying, we’ll make one important tweak to avoid compilation errors.

1. Go to the **Solidity Compiler** tab in the left sidebar
2. Expand **Advanced Configurations**.

   * Under **EVM Version**, select **Homestead** (this ensures smooth compatibility with HeLa’s runtime).

   **Your settings should look like this:**

<figure><img src="https://105378026-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FjMEkjypW9VmSM7QWnBno%2Fuploads%2FGG01PYRAj70i4L1WoGGD%2FRemix%20Conpile.png?alt=media&#x26;token=1ae98fa1-2981-4ba6-8620-0e8d3cd2e49e" alt=""><figcaption></figcaption></figure>

3. Now click **Compile**.
4. If the compilation succeeds, you’ll see a green check.

### **Step 4: Deploy to HeLa**

1. Navigate to the **Deploy & Run Transactions** tab
2. In the **Environment** dropdown, select **Browser** **Extension** > **Injected Provider - MetaMask**

> **Network Detection**
>
> If Injected Provider cannot detect the network, refresh the Remix IDE page and switch between networks in MetaMask.

3. Select your **MyToken** contract from the dropdown
4. Enter an initial supply (e.g., `100000`)
5. Click **Deploy** to deploy your ERC-20 token contract
6. Confirm the deployment transaction in MetaMask

<figure><img src="https://105378026-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FjMEkjypW9VmSM7QWnBno%2Fuploads%2FdCUHPFiEtGCMS2ocZjMz%2FRemix%20deploy.png?alt=media&#x26;token=fb0d12b6-b6a4-49c9-8d09-fe0a48409cfb" alt=""><figcaption></figcaption></figure>

### **Step 5: Get Contract Address**

1. After successful deployment, copy the **Contract Address** from Remix, from the terminal.

### **Step 6: Verify on Block Explorer**

1. In MetaMask, click on the transaction and select [**View on block explorer**](https://testnet-blockexplorer.helachain.com/)
2. Verify that the ERC-20 token transfer is displayed correctly on the explorer

### **Step 7: Import Token to MetaMask**

1. In MetaMask, go to **Tokens** tab and click **Import Tokens.**

<figure><img src="https://105378026-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FjMEkjypW9VmSM7QWnBno%2Fuploads%2FOkdDzmhCiapeLRfIuXYp%2Fremix%20import.png?alt=media&#x26;token=ca5a4f81-8bdc-4cbc-8880-cfbf265a2db3" alt=""><figcaption></figcaption></figure>

2. Paste the contract address from Remix into the **Token Contract Address** field
3. The token information should auto-populate (Token Symbol and Decimals)
4. Click **Add Custom Token** and then **Import Tokens**

### **Step 8: Verify Token Balance**

1. Check your **Tokens** tab in MetaMask to see your newly minted tokens
2. You should see 100000 tokens (or your custom amount) in your wallet

### **Step 9: Transfer Tokens**

1. Select your token in MetaMask and click **Send**
2. Enter the recipient address and amount
3. Click **Next** and confirm the transaction
4. Wait for the transaction to be confirmed

> **Testing Tips**
>
> * Test token transfers between different MetaMask accounts
> * Verify all transactions appear correctly on the block explorer
> * If you encounter issues, try resetting MetaMask via settings

### **Troubleshooting**

If you encounter issues:

* **Network not detected**: Refresh Remix and switch networks in MetaMask
* **Transaction fails**: Ensure you have sufficient HLUSD for gas fees
* **Token not appearing**: Double-check the contract address when importing
* **MetaMask issues**: Reset MetaMask via settings if problems persist

## Support :&#x20;

If you encounter any issues during setup or require assistance, please join the [**HeLa Developer Community**](https://discord.gg/NEBtTztJCj) for direct support and guidance.<br>