xCTR Staking

xCTR is an upgradeable ERC-4626 vault with voting power (ERC20Votes). It is non-transferable — transfer() and transferFrom() revert. Standard ERC-4626 withdraw() and redeem() also revert; use the exit system instead.

Specifications

Property	Value
Name	Staked CTR
Symbol	xCTR
Decimals	18
Standard	ERC-4626 + ERC20Votes (upgradeable)
Transferable	No
Clock Mode	Timestamp

Configuration

Parameter	Default	Description
epochPeriod	7 days	Reward streaming period
minExitDuration	15 days	Minimum wait before exit completion
maxExitDuration	90 days	Wait time for zero penalty
minExitPenaltyBps	0 (0%)	Penalty at max duration
maxExitPenaltyBps	5000 (50%)	Penalty at min duration
instantExitPenaltyBps	5000 (50%)	Fixed instant exit penalty

All parameters are updatable by the contract owner.

Staking

Deposit CTR to receive xCTR shares:

// Approve first
ctr.approve(xCTR_ADDRESS, amount);

// Deposit CTR, receive xCTR
uint256 shares = xCTR.deposit(amount, receiver);

// Or specify shares
uint256 assets = xCTR.mint(shares, receiver);

Shares are calculated at the current exchange rate (totalAssets / totalSupply). As rewards accrue, each xCTR becomes redeemable for more CTR.

Rewards

Rewards are streamed linearly over weekly epochs:

1. Rewards added via addRewards(amount) are queued for the next epoch

2. When a new epoch starts, queued rewards stream linearly over 7 days

3. Exit penalties are also added as rewards for remaining stakers

// Add external rewards (requires approval)
ctr.approve(xCTR_ADDRESS, rewardAmount);
xCTR.addRewards(rewardAmount);

Exit System

Start Exit

Burns xCTR shares and locks the CTR value at the current exchange rate:

uint256 exitId = xCTR.startExit(shares);

Each user can have multiple pending exits, each with its own ID and timeline. Exit parameters (penalty rates, durations) are snapshotted at start time — subsequent parameter changes don't affect existing exits.

Complete Exit (after day 15)

Penalty decreases linearly from 50% → 0% over the exit window:

xCTR.completeExit(exitId);

Penalty formula:

penaltyBps = minPenalty + (maxPenalty - minPenalty) × (maxDuration - elapsed) / (maxDuration - minDuration)

Cancel Exit (before day 15)

Returns xCTR at the current exchange rate (may differ from original amount):

xCTR.cancelExit(exitId);

Instant Exit

Immediate withdrawal with a fixed 50% penalty:

xCTR.instantExit(shares);

Read Functions

// xCTR balance
uint256 shares = xCTR.balanceOf(user);

// CTR value of shares
uint256 ctrValue = xCTR.convertToAssets(shares);

// Shares needed for a CTR amount
uint256 sharesNeeded = xCTR.convertToShares(ctrAmount);

// Total assets backing all xCTR
uint256 total = xCTR.totalAssets();

// Preview exit outcome
(uint256 assets, uint256 minDur, uint256 maxDur, uint256 minPen, uint256 maxPen) = xCTR.previewStartExit(shares);

// Preview completion at a given timestamp
(uint256 netAssets, uint256 penalty) = xCTR.previewCompleteExit(user, exitId, timestamp);

// Preview cancellation
(uint256 assets, uint256 sharesRestored) = xCTR.previewCancelExit(user, exitId);

// Penalty calculations
uint256 penalty = xCTR.getExitPenalty(assets, duration);
uint256 instantPenalty = xCTR.getInstantExitPenalty(assets);

Voting

xCTR integrates ERC20Votes for governance. Voting power equals xCTR balance but must be delegated to activate:

// Delegate to self
xCTR.delegate(msg.sender);

// Delegate to another address
xCTR.delegate(delegatee);

// Check voting power
uint256 votes = xCTR.getVotes(account);

// Historical voting power
uint256 pastVotes = xCTR.getPastVotes(account, timestamp);

Events

Event	Description
RewardsAdded(sender, amount, isPenalty)	Rewards queued for next epoch
ExitStarted(user, exitId, shares, assets)	Exit initiated
ExitCompleted(user, exitId, amount, penalty, duration)	Exit finalized
ExitCancelled(user, exitId, assets, sharesRestored)	Exit cancelled, xCTR restored
InstantExited(user, shares, amount, penalty)	Instant exit executed