import "@thirdweb-dev/contracts/extension/Staking20.sol";

The Staking20 smart contract extension implements ERC20 staking mechanism. With this extension, you can set up a staking contract for holders of your ERC20 tokens. Users can stake their tokens and earn a different set of ERC20 tokens as rewards.

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This is an example smart contract demonstrating how to inherit from this extension and override the functions to add (optional) custom functionality.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@thirdweb-dev/contracts/extension/Staking20.sol";
import "@thirdweb-dev/contracts/eip/interface/IERC20.sol";
import "@thirdweb-dev/contracts/eip/interface/IERC20Metadata.sol";

contract MyContract is Staking20 {
    // ERC20 Reward Token address. See {_mintRewards}.
    address public rewardToken;

    /**
     *  We store the contract deployer's address only for the purposes of the example
     *  in the code comment below.
     *
     *  Doing this is not necessary to use the `Staking20` extension.
     */
    address public deployer;

    constructor(
        uint256 _timeUnit,
        uint256 _rewardRatioNumerator,
        uint256 _rewardRatioDenominator,
        address _stakingToken,
        address _rewardToken,
        address _nativeTokenWrapper
    ) Staking20(
            _nativeTokenWrapper,
            _stakingToken,
            IERC20Metadata(_stakingToken).decimals(),
            IERC20Metadata(_rewardToken).decimals()
    ) {
        _setStakingCondition(_timeUnit, _rewardRatioNumerator, _rewardRatioDenominator);

        rewardToken = _rewardToken;
        deployer = msg.sender;
    }

    /**
     *  @dev    Mint/Transfer ERC20 rewards to the staker. Must override.
     *
     *  @param _staker    Address for sending rewards to.
     *  @param _rewards   Amount of tokens to be given out as reward.
     *
     */
    function _mintRewards(address _staker, uint256 _rewards) internal override {
        IERC20(rewardToken).transfer(_staker, _rewards);
    }

    // Returns whether staking restrictions can be set in given execution context.
    function _canSetStakeConditions() internal view override returns (bool) {
        return msg.sender == deployer;
    }
}

• Staking20Base