This is a section of the Cyfrin Foundry Solidity Course.
DSCEngine Example
Decentralized Stablecoin Example
Uses Openzeppelin-contracts version 4.8.3
This project is meant to be a stablecoin where users can deposit WETH and WBTC in exchange for a token that will be pegged to the USD.
The Foundry DeFi Stablecoin project aims to create a decentralized stablecoin that provides users with a reliable and efficient way to store value. By allowing users to deposit popular cryptocurrencies such as Wrapped Ether (WETH) and Wrapped Bitcoin (WBTC), the stablecoin maintains a peg to the US Dollar, ensuring stability in volatile markets. This project leverages smart contracts to automate the minting and redemption processes, providing a seamless user experience.
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Deposit Mechanism: Users can deposit WETH and WBTC to mint stablecoins, ensuring liquidity and ease of access.
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Pegged to USD: The stablecoin is designed to maintain a 1:1 peg with the US Dollar, providing users with a stable store of value.
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Decentralized Governance: The project incorporates decentralized governance mechanisms, allowing token holders to participate in decision-making processes.
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Security: Built on the Foundry framework, the project emphasizes security and reliability through rigorous testing and audits.
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User-Friendly Interface: The project aims to provide an intuitive interface for users to interact with the stablecoin, making it accessible to both novice and experienced users.
- git
- You'll know you did it right if you can run
git --version
and you see a response likegit version x.x.x
- You'll know you did it right if you can run
- foundry
- You'll know you did it right if you can run
forge --version
and you see a response likeforge 0.2.0 (816e00b 2023-03-16T00:05:26.396218Z)
- You'll know you did it right if you can run
git clone https://github.com/Cyfrin/foundry-defi-stablecoin-cu
cd foundry-defi-stablecoin-cu
forge build
If you can't or don't want to run and install locally, you can work with this repo in Gitpod. If you do this, you can skip the clone this repo
part.
- The latest version of openzeppelin-contracts has changes in the ERC20Mock file. To follow along with the course, you need to install version 4.8.3 which can be done by
forge install openzeppelin/openzeppelin-contracts@v4.8.3 --no-commit
instead offorge install openzeppelin/openzeppelin-contracts --no-commit
make anvil
This will default to your local node. You need to have it running in another terminal in order for it to deploy.
make deploy
We talk about 4 test tiers in the video.
- Unit
- Integration
- Forked
- Staging
In this repo we cover #1 and Fuzzing.
forge test
forge coverage
and for coverage based testing:
forge coverage --report debug
- Setup environment variables
You'll want to set your SEPOLIA_RPC_URL
and PRIVATE_KEY
as environment variables. You can add them to a .env
file, similar to what you see in .env.example
.
PRIVATE_KEY
: The private key of your account (like from metamask). NOTE: FOR DEVELOPMENT, PLEASE USE A KEY THAT DOESN'T HAVE ANY REAL FUNDS ASSOCIATED WITH IT.- You can learn how to export it here.
SEPOLIA_RPC_URL
: This is url of the sepolia testnet node you're working with. You can get setup with one for free from Alchemy
Optionally, add your ETHERSCAN_API_KEY
if you want to verify your contract on Etherscan.
- Get testnet ETH
Head over to faucets.chain.link and get some testnet ETH. You should see the ETH show up in your metamask.
- Deploy
make deploy ARGS="--network sepolia"
Instead of scripts, we can directly use the cast
command to interact with the contract.
For example, on Sepolia:
- Get some WETH
cast send 0xdd13E55209Fd76AfE204dBda4007C227904f0a81 "deposit()" --value 0.1ether --rpc-url $SEPOLIA_RPC_URL --private-key $PRIVATE_KEY
- Approve the WETH
cast send 0xdd13E55209Fd76AfE204dBda4007C227904f0a81 "approve(address,uint256)" 0x091EA0838eBD5b7ddA2F2A641B068d6D59639b98 1000000000000000000 --rpc-url $SEPOLIA_RPC_URL --private-key $PRIVATE_KEY
- Deposit and Mint DSC
cast send 0x091EA0838eBD5b7ddA2F2A641B068d6D59639b98 "depositCollateralAndMintDsc(address,uint256,uint256)" 0xdd13E55209Fd76AfE204dBda4007C227904f0a81 100000000000000000 10000000000000000 --rpc-url $SEPOLIA_RPC_URL --private-key $PRIVATE_KEY
You can estimate how much gas things cost by running:
forge snapshot
And you'll see an output file called .gas-snapshot
To run code formatting:
forge fmt
slither :; slither . --config-file slither.config.json
- That is an official repo maintained by the same org
- It downloads from the official release cycle
chainlink/contracts
use (npm) and packages it nicely for digestion from foundry.