KipuBank Smart Contract Project

Description

KipuBank is a smart contract built on the Ethereum blockchain as part of a Web3 developer assessment. This project demonstrates fundamental Solidity concepts, security best practices, and a professional development workflow using Foundry.

The contract allows users to:

• Deposit native ETH into a personal vault.
• Withdraw ETH from their vault, up to a fixed, per-transaction limit.
• Operate within a global deposit cap for the entire bank.

This project emphasizes security, readability, and clear documentation, adhering to the "Checks-Effects-Interactions" pattern and using custom errors and modifiers.

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Project Structure

This project uses the Foundry framework. The main contract is located in the /contracts directory.

• /contracts: Contains the KipuBank.sol smart contract.
• /test: Contains the complete test suite (KipuBank.t.sol).
• /script: Contains the deployment script (DeployKipuBank.s.sol).

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Getting Started

To get a local copy up and running, follow these simple steps.

Prerequisites

You will need the following tools installed on your machine:

• Git
• Foundry (Forge & Cast)

Installation & Setup

1. Clone the repository:

   git clone [https://github.com/](https://github.com/)[SEU_USUARIO_GITHUB]/[NOME_DO_REPOSITORIO].git
   cd [NOME_DO_REPOSITORIO]

2. Build the project: This command will compile the smart contracts.

   forge build

3. Run the tests: This command will run the entire test suite located in the /test folder.

   forge test -vv

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Deployment

The contract is designed to be deployed on a testnet (e.g., Sepolia).

1. Set up your environment: Create a .env file in the root directory and add the following variables:

   export SEPOLIA_RPC_URL="YOUR_ALCHEMY_OR_INFURA_RPC_URL"
   export PRIVATE_KEY="0xYOUR_WALLET_PRIVATE_KEY"
   export ETHERSCAN_API_KEY="YOUR_ETHERSCAN_API_KEY"
   
   # Constructor Arguments (in wei)
   export BANK_CAP=100000000000000000000
   export WITHDRAWAL_LIMIT=1000000000000000000
   

2. Run the deployment script: Load the environment variables and run the deployment script.

   source .env
   forge script script/DeployKipuBank.s.sol:DeployKipuBank --rpc-url $SEPOLIA_RPC_URL --private-key $PRIVATE_KEY --broadcast --verify -vvvv

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How to Interact with the Contract

The KipuBank contract has the following core functions:

• deposit(): (Payable) Allows any user to deposit ETH. Reverts if the amount is zero or if the bank cap is exceeded.
• withdraw(uint256 _amount): Allows a user to withdraw ETH from their balance. Reverts if the amount is zero, exceeds the withdrawal limit, or if the user has insufficient funds.
• getBalanceOf(address _user): (View) Returns the current ETH balance of any specified user address within the contract.
• i_withdrawalLimit: (Public View) Shows the immutable withdrawal limit per transaction.
• i_bankCap: (Public View) Shows the immutable total bank cap.

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Author

• Heitor Valim
• GitHub: https://github.com/heitorvalim7