Deploying Contracts

This guide explains how to deploy contracts on Starknet using the useUniversalDeployerContract hook in combination with useSendTransaction.

Overview

The Universal Deployer Contract (UDC) is a utility contract that allows you to deploy new contracts on Starknet. The useUniversalDeployerContract hook provides an easy way to interact with the UDC.

Usage

1. Get the UDC Instance

First, import and use the useUniversalDeployerContract hook:

import { useUniversalDeployerContract } from "@starknet-react/core";
 
function YourComponent() {
  const { udc } = useUniversalDeployerContract();
}

2. Prepare the Transaction

Use useSendTransaction to prepare and execute the contract deployment. You'll need:

classHash: The hash of the contract class you want to deploy
salt: A number used to generate the contract's address
fromZero: Boolean flag for address calculation
calldata: Constructor arguments for your contract

import { useSendTransaction } from "@starknet-react/core";
import { CallData } from "starknet";
 
function DeployContract() {
  const { udc } = useUniversalDeployerContract();
 
  const { send, isPending, error, data } = useSendTransaction({
    calls: udc
      ? [
          udc.populate("deploy_contract", [
            classHash,
            salt,
            fromZero,
            constructorCalldata,
          ]),
        ]
      : undefined,
  });
}

3. Complete Example

Here's a complete example showing how to deploy an ERC20 token:

import {
  useUniversalDeployerContract,
  useSendTransaction,
} from "@starknet-react/core";
import { CallData } from "starknet";
 
function DeployERC20() {
  const { address } = useAccount();
  const { udc } = useUniversalDeployerContract();
 
  const { send, isPending, error, data } = useSendTransaction({
    calls:
      udc && address
        ? [
            udc.populate("deploy_contract", [
              ERC20_CLASS_HASH,
              23, // salt
              false, // fromZero
              getConstructorCalldata(address),
            ]),
          ]
        : undefined,
  });
 
  return (
    <button onClick={() => send()} disabled={isPending}>
      {isPending ? "Deploying..." : "Deploy ERC20"}
    </button>
  );
}

API Reference

useUniversalDeployerContract

function useUniversalDeployerContract(props?: {
  address?: Address; // Optional: Override default UDC address
  provider?: ProviderInterface | null; // Optional: Custom provider
}): {
  udc: Contract; // The UDC contract instance
};

Deploy Contract Parameters

The deploy_contract function takes the following parameters:

class_hash: The hash of the contract class to deploy
salt: A number used to generate a unique contract address
from_zero: Boolean flag that affects address calculation
calldata: Constructor arguments for the contract being deployed

Notes

Make sure you're connected to the correct network before deploying
The UDC has a default address that's used if none is provided
Constructor calldata must be properly formatted according to your contract's ABI
Transaction fees will apply for contract deployment

Error Handling

Always handle potential errors during deployment:

const { error, isError, send } = useSendTransaction({
  // ... configuration
});
 
if (isError) {
  console.error("Deployment failed:", error.message);
}

For a complete working example, check out our deployment demo.