Protocol Review

The setTaxRate function allows for a tax as high as 99.99% to be imposed, which can lead to near total loss of funds for users.

Require a more strict cap on the taxRate and/or timelock the setTaxRate function.

The governanceRecoverUnsupported function uses transfer which provides a return value that should be checked. Not all ERC20 implementations revert in case of failure, so it is important to have some logic in the event these executions fail.

Check the return value, or opt for a safeTransfer alternative.

Possibly dangerous reliance on block.timestamp. block.timestamp can be manipulated by validators.

Rely on block.number instead, or ensure resilience to block.timestamp manipulation.

The communityFundAllocation, devFundAllocation, vestingDuration, startTime, endTime, communityFundRewardRate, and devFundRewardRate variables are only set in the constructor, and should therefore be declared immutable.

Declare them as immutable.

Possibly dangerous reliance on block.timestamp. block.timestamp can be manipulated by validators.

Rely on block.number instead, or ensure resilience to block.timestamp manipulation.

The pool variable is often declared storage when it is not modified.

Declare it as memory to save on gas.

The hamster and poolStartTime variables are only set in the constructor, and should therefore be declared immutable.

Declare them as immutable.

The operator can use add to extend the poolInfo list. If poolInfo becomes significantly long it can cause high gas consumption for the governanceRecoverUnsupported, massUpdatePools, checkPoolDuplicate, add, and set functions.

If the gas consumption were to exceed the transaction limit as a result, these functions would be rendered useless.

Timelock the add function or limit the maximum size of poolInfo.

Using setLockup, the operator can arbitrarily set the withdrawLockupEpochs and rewardLockupEpochs as high as 56 epochs retroactively after an address has locked.

Timelock the setLockup sufficiently such that all current locks can become unlocked before the new lockup is applied, or refactor the logic such that the new lockup only applies to new lockers.

The setOperator and setLockup functions change state that affects stakeholders so they should emit corresponding events.

Add event emissions to setOperator and setLockup.

The hamster and poolStartTime variables are only set in the constructor, and should therefore be declared immutable.

Declare them as immutable.

The operator address is not a multi-sig and has potentially dangerous permissions for hamsterWheelSetOperator, hamsterWheelAllocateSeigniorage, hamsterWheelSetLockUp, setBondDepletionFloorPercent, setBootstrap, setDiscountPercent, setExtraFunds, setHamsterOracle, setHamsterPriceCeiling, setHamsterWheel, setMaxDebtRatioPercent, setMaxExpansionTiersEntry, setMaxPremiumRate, setMaxSupplyContractionPercent, setMaxSupplyExpansionPercents, setMintingFactorForPayingDebt, setPremiumPercent, setPremiumThreshold, setSupplyTiersEntry

Make the operator a multi-sig and/or introduce a timelock for the community to monitor events.

The hamster and router variables are only set in the constructor, and should therefore be declared immutable for gas optimization.

Declare them as immutable.

If setTaxExclusionForAddress was called by the operator and set to true for an address, that address can call taxFreeTransferFrom with an excluded sender. Afterwards, the sender would be included in the tax.

Introduce a timelock such that the community can monitor what the operator sets.

The addLiquidityTaxFree function uses transfer which provides a return value that should be checked. Not all ERC20 implementations revert in case of failure, it is important to have some logic in the event these executions fail.

Check the return value, or opt for a safeTransfer alternative.

The operator address is not a multi-sig and has potentially dangerous permissions for disableAutoCalculateTax, enableAutoCalculateTax, excludeAddressFromTax, includeAddressInTax, setBurnThreshold, setTaxCollectorAddress, setTaxExclusionForAddress, setTaxRate, setTaxTiersRate, setTaxTiersTwap, setTaxableHamsterOracle, transferTaxOffice

Most notably transferTaxOffice sets the taxOffice for the hamster contract, potentially compromising the hamster taxOffice permissioned functions as well.

Make the operator a multi-sig and/or introduce a timelock for the community to monitor events.

The disableAutoCalculateTax, enableAutoCalculateTax, excludeAddressFromTax, includeAddressInTax, setBurnThreshold, setTaxCollectorAddress, setTaxExclusionForAddress, setTaxRate, setTaxTiersRate, setTaxTiersTwap, setTaxableHamsterOracle, transferTaxOffice functions change state that affects stakeholders so they should emit corresponding events.

Add event emissions to these functions.