Quick start

In this guide we will deploy a simple smart contract onto Reef chain.

(Optional) Setting up a development node#

To set up your local development or RPC node, check out the Reef node guide.

Alternatively, you can skip this and just use the public RPC’s (either directly) or through our Javascript and Python libraries.

New to Solidity?#

Solidity is a programming language for writing DeFi applications. The Solidity programs are compiled and uploaded to Reef chain, where they run in a completely decentralized fashion.

Here are some great resources for learning Solidity:

• The official Solidity docs
• Solidity tutorial for programmers

Compiling, deploying and managing Solidity smart contracts by hand can be a chore. For this reason we have developer frameworks for Python and JS/TypeScript.

Smart Contracts on Reef vs Ethereum#

The Reef chain smart contracts are written in Solidity. Any existing Ethereum smart contracts written in Solidity 0.6 or greater will work on Reef chain without a need for modifications.

However some of the tooling from Ethereum will NOT work on Reef chain due to inherent differences in the blockchain architecture.

Fortunately we have drop in replacements for most commonly used tools.

Deploy your first ERC-20 Token#

We are going to pick a simple ERC-20 contract for our demo, but feel free to try out other examples as well.

In this guide we are using Reef Hardhat, which is suitable for more experienced developers. If you would like to deploy your contract via an easy to use web IDE, try Reef Remix.

Clone the examples repo#

git clone https://github.com/reef-chain/hardhat-reef-examples-examples

Install the dependencies#

yarn

Run the deployment script#

npx hardhat run scripts/erc20/deploy.js

Interact with the ERC-20 to send tokens#

We can call functions on our smart contract through the Hardhat interface:

const hre = require("hardhat");

async function main() {
  // Bob is the owner of Token contract and he wants to send some token amount to dave
  const bob = await hre.reef.getSignerByName("bob");
  const dave = await hre.reef.getSignerByName("dave");

  // Extracting user addresses
  const bobAddress = await bob.getAddress();
  const daveAddress = await dave.getAddress();

  // Token contract address
  const tokenAddress = "0x4a4fA87b810A30BE84a3a30318D6D9feEae126e5";

  // Retrieving Token contract from chain
  const token = await hre.reef.getContractAt("Token", tokenAddress, bob);

  // Let's see Dave's balance
  let daveBalance = await token.balanceOf(daveAddress);
  console.log(
    "Balance of to address before transfer:",
    await daveBalance.toString()
    );

  // Bob transfers 10000 tokens to Dave
  await token.transfer(daveAddress, 10000);

  // Let's once again check Dave's balance
  daveBalance = await token.balanceOf(daveAddress);
  console.log(
    "Balance of to address after transfer:",
    await daveBalance.toString()
  );

  // Bob's amount after transactions
  const bobBalance = await token.balanceOf(bobAddress);
  console.log(
    "Balance of from address after transfer:",
    await bobBalance.toString()
  );
}

main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

Next steps#

Congratulations. You now have a running development node with the first smart contract. You and now are ready to start building your first DeFi app.

Deploy on testnet#

Deploying on testnet is similar to development, however there are 2 things we need.

1.) Run a testnet node or use the public testnet RPC.

2.) Create an account and obtain testnet REEF tokens from the faucet.

To get 2000 REEF testnet tokens, join us in Reef’s Discord server. Verify your account, then select the Builder role in 📋┊start-here. You will get access to the Reef chain testnet faucet in 🚰┊faucet.

Deploy on mainnet#

Deploying on mainnet is similar to development, however there are 2 things we need.

1.) Run a mainnet node or use the public mainnet RPC.

2.) Create an account and obtain Reef chain native REEF tokens from the bridge or exchange.

Verify the contract on Reefscan#

Once you have deployed your smart contract on Reef Chain mainnet (or testnet), you will want to verify it on Reefscan, so that other developers can access its source code and ABI.

Verify your deployed contract on: Mainnet or Testnet

Build an UI#

If you would like to build an app quickly from pre-made components, check out the Reef UI kit for React, Vue and Angular.

To start building a custom UI for your DApp, check the Reef UI Kit repository. It provides the most commonly used UI components and elements to create your DApp with ease.