OptyFi-Lido Adapter

The integration of Lido's Ethereum staking pool using OptyFi's DeFi Adapter interface. With this integration, OptyFi users should be able to deposit their ETH into OptyFi's ETH vault which will in turn stake them into the Lido protocol to receive yield-bearing stETH tokens.

Video walkthrough: https://www.youtube.com/watch?v=-0ZPnGmrmJY

Deployment address on Rinkeby: 0x289cd4c7B1cbeAC268dB5c62Be89bF2f1d93AA84

Prerequisites

• Install Node JS >= v12.0.0
• Learn Javascript and Typescript
• Learn Solidity >=v0.6.12.
• Learn smart contract development environment like Hardhat
• Learn testing framework like mocha
• Learn assertion library like chai

And passion for financial freedom...

Getting started

Development Setup

• Create a .env file and set a BIP-39 compatible mnemonic as an environment variable. Follow the example in .env.example. If you don't already have a mnemonic, use this website to generate one.
• You will require access to archive Node URL for forking the mainnet.

Proceed with installing dependencies:

yarn install

What is a DeFiAdapter

• DeFi adapter is a vital building block for executing opty.fi's network of strategies.
• Specifications for DeFi adapter help perform :
  • transactions like deposit, withdraw, staking, un-staking, adding liquidity, claim reward and harvesting of the reward.
  • read calls for liquidity pool token contract address, liquidity pool token balance, staked token balance, balance in underlying token of both staked and non-staked liquidity pool token, unclaimed reward tokens and reward token contract address
• A DeFi Adapter smart contract requires implementation of following interfaces :
  • IAdapter.sol (Mandatory)
  • IAdapterHarvestReward.sol (Optional)
  • IAdapterStaking.sol (Optional)
  • IAdapterBorrow.sol (Optional)
  • IAdapterInvestmentLimit.sol (Optional)

Pro Tip : Inherit IAdapterFull interface from IAdapterFull.sol to Adapter Contract if the protocol you choose required implementation of all the above interfaces.

Developing DeFiAdapter

Step #1 - Use this template

• This is a GitHub template, so click on green button "Use this template" on the top-right corner of the page to create new defi adapter.

Step #2 - Pool, LP token and underlying token(s) address gathering

• Choose a DeFi protocol and gather the pool contract addresses similar to harvest.finance-pools.json.

Step #3 - Implementing IAdapter interface

• Implement an adapter contract using above interface(s) similar to HarvestFinanceAdapter.sol

Step #4 - Unit Tests

• Write unit tests for all the functions across all the pool contracts gathered in Step 1.
• You might want to use a test utility contract like TestDeFiAdapter for creating a sandbox environment to execute the transaction based on function signature and target address returned from getCodes()-style functions from DeFiAdapter.
• All other functions can be directly tested from the DeFiAdapter contract.
• The unit test for HarvestFinanceAdapter.sol can be found in HarvestFinanceAdapter.ts

Useful commands

Usage	Command
Compile the smart contracts with Hardhat	$ yarn compile
Compile the smart contracts and generate TypeChain artifacts	$ yarn typechain
Lint the Solidity Code	$ yarn lint:sol
Lint the TypeScript Code	$ yarn lint:ts
Run the Mocha tests	$ yarn test
Generate the code coverage report	$ yarn coverage
Delete the smart contract artifacts, the coverage reports and the Hardhat cache	$ yarn clean
Deploy the adapter to Hardhat Network	$ yarn deploy

Syntax Highlighting

If you use VSCode, you can enjoy syntax highlighting for your Solidity code via the vscode-solidity extension. The recommended approach to set the compiler version is to add the following fields to your VSCode user settings:

{
  "solidity.compileUsingRemoteVersion": "v0.6.12+commit.27d51765",
  "solidity.defaultCompiler": "remote"
}

Where of course v0.6.12+commit.27d51765 can be replaced with any other version.

References

• Hardhat
• Ethereum Development Documentation