PoolTogether V5 Prize Pool Twab Rewards

The Prize Pool Twab Rewards contract allows anyone to distribute tokens to all contributors to a PoolTogether Prize Pool.

Testnet Deployment

Optimism Sepolia

Tx of Promotion 1

How it Works

Typically Prize Pool "contributors" are vaults that hold user deposits and contribute the yield to the Prize Pool. The Prize Pool Twab Rewards contract distributes incentives to those users.

The contract divides time into "epochs" over which contributions are measured. To compute a user's rewards for a given epoch:

usersVaultBalance = the average balance they held during the epoch (pulled from the TwabController)
vaultTotalSupply = the average total supply for a vault during the epoch (pulled from the TwabController)

vaultContributions = the vault's contributions to the prize pool during the epoch (pulled from the PrizePool)
totalContributions = the total contributions to the prize pool during the epoch (pulled from the PrizePool)

userRewards = (usersVaultBalance / vaultTotalSupply) * (vaultContributions / totalContributions) * tokensPerEpoch

So each user's portion of the rewards is equivalent to their portion of the vault * the vaults portion of contributions to the prize pool.

• TwabController on Github
• Prize Pool on Github

Usage

Creating the Promotion

The contract supports any number of incentive "promotions". You can create a promotion by calling:

function createPromotion(
    IERC20 token,
    uint40 startTimestamp,
    uint104 tokensPerEpoch,
    uint40 epochDuration,
    uint8 numberOfEpochs
) external returns (uint256);

Parameter	Description
token	The token to distribute.
startTimestamp	The timestamp at which the promotion begins. The value MUST align with a draw start or end in the Prize Pool.
tokensPerEpoch	The number of tokens to distribute for an epoch. An epoch is the duration of time over which contributions are measured and incentives doled out proportionally
epochDuration	The length of time of the epoch in seconds. The value MUST be a multiple of the draw period in the Prize Pool.
numberOfEpochs	The number of epochs that the promotion will run for.

Calling createPromotion will transfer the tokens from the caller to the contract. The caller must have already approved the token spend. The amount of spend is tokensPerEpoch * numberOfEpochs.

The function returns the promotion id.

Example

Let's say I want to distribute 1000 WETH per week for 10 weeks. Assuming the start time and duration are draw-aligned, I would call createPromotion with:

uint256 promotionId = createPromotion(
    wethAddress,
    86400,
    1000e18,
    86400,
    10
);

Claiming Rewards

Anyone may claim rewards for a user by calling claimRewards:

function claimRewards(address vault, address user, uint256 promotionId, uint8[] calldata epochIds) external returns (uint256);

Param	Description
vault	The contributor to the prize pool (usually a vault)
user	The user whose balance should be looked up in the TwabController
promotionId	The id of the promotion to claim for
epochsIds	An array of the epochs to claim

The function returns the total rewards claimed.

Example

Let's say a user of a vault wishes to claim the rewards for the above create promotion example. Assuming they deposited into the vault halfway through the promotion, they would call claimRewards like so:

uint totalRewards = claimRewards(vaultAddress, userAddress, promotionId, [5, 6, 7, 8, 9]);

Note that this is pseudocode: arrays cannot be defined inline in Solidity!

Development

Installation

You may have to install the following tools to use this repository:

• Foundry to compile and test contracts
• direnv to handle environment variables
• lcov to generate the code coverage report

Install dependencies:

npm i

Env

Copy .env.example and write down the env variables needed to run this project.

cp .env.example .env

Once your env variables are setup, load them with:

direnv allow

Compile

Run the following command to compile the contracts:

npm run compile

Coverage

Forge is used for coverage, run it with:

npm run coverage

You can then consult the report by opening coverage/index.html:

open coverage/index.html

Code quality

Husky is used to run lint-staged and tests when committing.

Prettier is used to format TypeScript and Solidity code. Use it by running:

npm run format

Solhint is used to lint Solidity files. Run it with:

npm run hint

CI

A default Github Actions workflow is setup to execute on push and pull request.

It will build the contracts and run the test coverage.

You can modify it here: .github/workflows/coverage.yml

For the coverage to work, you will need to setup the MAINNET_RPC_URL repository secret in the settings of your Github repository.