Hello ZKsync!

npm run compile

Upon successful compilation, you'll receive output detailing the typings and Solidity files compiled.

Generating typings for: 20 artifacts in dir: typechain-types for target: ethers-v6
Successfully generated 78 typings!
Compiled 20 Solidity files successfully

The compiled artifacts will be located in the /artifacts folder.

Run a local node

For this section, we will deploy to a local Hardhat node. Run the command below to start a persistent in-memory node:

npx hardhat node

Configuring a Hardhat Wallet

Since we are using a local Hardhat in-memory node for development, we can use one of the rich wallets for transactions and deployments.

Copy one of the private keys logged after starting the node to the .env file, using the .env.example file as an example.

Deploy the contract

The deployment script is located at /deploy/1-hello-zksync/deploy.ts.

npm run deploy:hello-zksync

Upon successful deployment, you'll receive output showing the contract name and address.

Deploying CrowdfundingCampaign contract to localhost
CrowdfundingCampaign deployed to 0x5FbDB2315678afecb367f032d93F642f64180aa3

Interact with contract

Let's try interacting with the deployed contract.

In the deploy/1-hello-zksync/interact.ts script, use your deployed contract address for the CONTRACT_ADDRESS variable.

Then, run the script:

npm run interact:hello-zksync

Congratulations! You've deployed a crowdfunding contract and learned how to interact with the deployed contract using Hardhat!

Run the compile script from your project in the terminal:

npm run compile

Upon successful compilation, you'll receive output detailing the zksolc and solc versions used during compiling and the number of Solidity files compiled.

Compiling contracts for ZKsync Era with zksolc v1.5.13 and solc v0.8.17
Compiling 15 Solidity files
Successfully compiled 15 Solidity files

The compiled artifacts will be located in the /artifacts-zk folder.

Setup local node

This series of guides will use in-memory anvil-zksync node which allows for quicker testing and debugging processes. A great benefit of using a local node is that you will avoid incurring any actual transaction costs as the node provides a set of rich wallets that come with more than enough ETH to use for development.

Run a local node

To run a local in-memory anvil-zksync node on your machine, you will need Docker running. The easiest way to start Docker is to run the Docker Desktop app.

We are going to use the "in-memory node" module for our local node setup.

1. Run the following command in your terminal:

   zksync-cli dev config
   

   
   It will provide a list of available node types you can run locally.
2. Use the arrow keys to navigate to "in-memory node" and press Enter to select. The next question will ask what additional modules you want to use. Make sure additional modules are unselected for this setup and press Enter to finish the configuration.

   ? Node to use (Use arrow keys)
   ❯ in-memory node - Quick startup, no persisted state, only L2 node - zkcli-in-memory-node
     Dockerized node - Persistent state, includes L1 and L2 nodes - zkcli-dockerized-node
   (Move up and down to reveal more choices)
   

   
   The in-memory node module will run a lighter version of the ZKsync Era node which is ideal for swift testing, prototyping, bootloader and system contract testing.
3. Run the following command in your terminal to start up the node:

   zksync-cli dev start
   

   
   anvil-zksync node includes pre-configured rich wallets for use, see anvil-zksync rich wallets.

Your anvil-zksync node is accessible at http://127.0.0.1:8011, ready for deployment or testing purposes. You can use the Docker Desktop app to view logs from the running ZKsync Era node or use the zksync-cli dev logs command.

When you are done running your anvil-zksync node, you can stop it with zksync-cli dev stop. You can learn more about managing a local node with ZKsync CLI on Running a node.

Configuring a Hardhat Wallet

Since we are using a local in-memory anvil-zksync node for development, we can use one of the rich wallets for transactions and deployments.

Copy the private key for the first rich wallet from .env.example to the .env file.

Deploy the contract

The deployment script is located at /deploy/1-hello-zksync/deploy.ts.

npm run deploy:hello-zksync

Upon successful deployment, you'll receive output detailing the deployment process, including the contract address, source, and encoded constructor arguments:

Starting deployment process of "CrowdfundingCampaign"...
Estimated deployment cost: 0.0065057128 ETH

"CrowdfundingCampaign" was successfully deployed:
 - Contract address: 0x26b368C3Ed16313eBd6660b72d8e4439a697Cb0B
 - Contract source: contracts/1-hello-zksync/CrowdfundingCampaign.sol:CrowdfundingCampaign
 - Encoded constructor arguments: 0x00000000000000000000000000000000000000000000000000470de4df820000

Read from the contract using ZKsync CLI

We can confirm the amount by calling the getFundingGoal method using ZKsync CLI.

In the terminal, run the following in your project directory, replacing the contract address with your contract's address:

zksync-cli contract read \
--chain in-memory-node \
--contract <0xYOUR_CONTRACT_ADDRESS> \
--abi artifacts-zk/contracts/1-hello-zksync/CrowdfundingCampaign.sol/CrowdfundingCampaign.json

The CLI will prompt you with a list of available methods to select from. Navigate with the arrow keys and press Enter on the method getFundingGoal().

Using provided ABI file
? Contract method to call (Use arrow keys)
  ──────────────── Provided contract ────────────────
❯ getFundingGoal() view returns (uint256)
  getTotalFundsRaised() view returns (uint256)
  owner() view returns (address)
  ───────────────────────────────────────────────────
  Type method manually

• The --chain option defines the network we want to use, which is our local in-memory node.
• The --contract is the address of the contract you just deployed.
• The --abi provides the ABI to decode the contract and provide the list of methods to select from. Without the ABI provided, you will have to manually type out the method name.

You will get a response with the amount that we passed in to the constructor on deploy:

? Contract method to call getFundingGoal() view returns (uint256)

✔ Method response (raw): 0x00000000000000000000000000000000000000000000000000470de4df820000
✔ Decoded method response: 20000000000000000

Write to the contract using ZKsync CLI

Let's fund this crowdfunding campaign and make Zeek happy!

We will write to the contract using ZKsync CLI, which requires a private key. In this demonstration we will use the second wallet provided in the list of rich wallets.

In the terminal, run the following command with your deployed contract's address:

zksync-cli contract write \
--chain in-memory-node \
--contract <0xCONTRACT_ADDRESS> \
--abi artifacts-zk/contracts/1-hello-zksync/CrowdfundingCampaign.sol/CrowdfundingCampaign.json \
--pk <0xDEPLOYER_PRIVATE_KEY> \
--value 0.5

In the prompt, press Enter on the contribute() payable method. The CLI will then output the transaction information upon success.

We can read the transaction data of the contribution with the following:

zksync-cli transaction info \
--tx <0xTRANSACTION_HASH> \
--chain in-memory-node

Our crowdfund has reached its funding goal! Let's withdraw the funds for the owner:

zksync-cli contract write \
--chain in-memory-node \
--contract <0xCONTRACT_ADDRESS> \
--pk <0xDEPLOYER_PRIVATE_KEY>

The CLI will prompt for the method to call, we will call withdrawFunds():

? Enter method to call withdrawFunds()

Congratulations! You've deployed a crowdfunding contract and learned how to interact with the deployed contract using ZKsync CLI!