FeeCollector - Stockline

FeeCollector receives protocol revenue and splits it into a reserve and a treasury. Interest cash arrives from Stockline on repay; liquidation fees arrive as seized stock tokens and are sold for USDG with sweepCollateral. Unallocated USDG fills the reserve up to a target of 5% of pool borrows, then flows to the treasury. Anyone can spend the reserve on pool bad debt and burn treasury USDG into STK within an epoch budget. FeeCollector lets you:

Allocate fresh USDG into reserve, then treasury
Cover pool bad debt from the reserve
Buy and burn STK with treasury USDG inside the epoch budget
Sell seized collateral for USDG along its zap route
Credit reserve and treasury directly (used by CreatorFeeRouter)
Read the reserve, treasury, target, and epoch state

Addresses per network. Every address is also on Addresses.

Network	Address
Robinhood Chain testnet	0x35609322D14dDb08fFAAf844c4a02afAcC586D77

The source code is src/core/FeeCollector.sol on GitHub. The ABI is /abis/FeeCollector.json.

Write methods

notifyInterest

function notifyInterest(uint256 amount) external

Records that amount of reserve-factor interest has accrued. Only Stockline can call it. This is a counter; the cash arrives later on repay.

Core only.

Input parameters

Name	Type	Description
amount	`uint256`	USDG interest reserved for the protocol.

notifyLiquidationFee

function notifyLiquidationFee(uint256 amount) external

Records that amount of seized collateral arrived as the protocol’s liquidation share. Only Stockline can call it.

Core only.

Input parameters

Name	Type	Description
amount	`uint256`	Collateral tokens received, in native units.

credit

function credit(uint256 toReserve, uint256 toTreasury) external nonReentrant

Pulls toReserve + toTreasury USDG from the caller and credits the two buckets directly, skipping the target waterfall. Permissionless. CreatorFeeRouter uses it for the 40/30 split. Reverts with ZeroAmount when both are zero.

The caller must approve FeeCollector for the total. USDG sent here belongs to the protocol.

Direct credits skip the allocate waterfall so a Pons split can raise reserve even when the 5% target is already full.

Input parameters

Name	Type	Description
toReserve	`uint256`	USDG credited to the reserve.
toTreasury	`uint256`	USDG credited to the treasury.

setReserveTargetPct

function setReserveTargetPct(uint64 pct) external

Sets the reserve target as a share of pool.borrowed(). Owner only. Reverts with InvalidWad above 1e18.

Owner (timelock) only.

Input parameters

Name	Type	Description
pct	`uint64`	Target share in WAD. Deployed value is 0.05e18 (5%).

setBurnEpoch

function setBurnEpoch(uint32 duration) external

Sets the length of each buy-and-burn epoch. Owner only. Reverts with InvalidEpoch outside [1 day, 90 days].

Owner (timelock) only.

Input parameters

Name	Type	Description
duration	`uint32`	Epoch length in seconds. Deployed value is 7 days.

allocate

function allocate() public

Moves any USDG not yet assigned to reserve or treasury: first fills the reserve up to reserveTarget, then sends the rest to the treasury. Permissionless. Emits Allocated only when something moved.

coverBadDebt

function coverBadDebt(uint256 amount) external nonReentrant

Spends up to amount of the reserve into USDGPool through restore, making suppliers whole after a write-off. Permissionless. Allocates first. Reverts with ZeroAmount when amount is 0 or the reserve is empty.

This does not check that the pool actually had bad debt. It always increases pool cash and the sUSDG share price.

Input parameters

Name	Type	Description
amount	`uint256`	Maximum USDG to move. Capped at the current reserve.

buyAndBurn

function buyAndBurn(uint256 amount) external nonReentrant

Swaps amount treasury USDG along the buy-and-burn route and sends the output token to the dead address. Permissionless. Reverts with EpochBudgetExceeded above the unused epoch budget, InsufficientTreasury above the treasury balance, CapExceeded above maxPerCall, and InvalidRoute if the route does not start with USDG.

Each epoch’s budget is 20% (2000 bps, fixed) of the treasury at roll time. The first epoch after deployment has a budget of 0, so burns can start only after the first roll. Slippage is checked against the router’s TWAP quote.

Input parameters

Name	Type	Description
amount	`uint256`	USDG to spend, in USDG native units.

sweepCollateral

function sweepCollateral(address token) external nonReentrant

Sells the whole balance of a seized collateral token for USDG using its zap route, then allocates. Permissionless. Reverts with InvalidRoute for USDG or a route that does not end in USDG, NotAllowed if the token has no allowed route, and ZeroAmount when the balance is 0. Input parameters

Name	Type	Description
token	`address`	The collateral token to sell.

Read methods

reserveTarget

function reserveTarget() public view returns (uint256)

Returns the reserve the waterfall fills before the treasury: pool.borrowed() * reserveTargetPct / 1e18. Return values

Type	Description
`uint256`	USDG amount.

unallocated

function unallocated() public view returns (uint256)

Returns USDG held here that is not yet assigned to reserve or treasury. Return values

Type	Description
`uint256`	USDG amount.

Events

Allocated

event Allocated(uint256 toReserve, uint256 toTreasury)

Fires when unallocated USDG moves into reserve and treasury.

Credited

event Credited(uint256 toReserve, uint256 toTreasury)

Fires when someone credits reserve and treasury directly.

ReserveTargetPctSet

event ReserveTargetPctSet(uint64 pct)

Fires when the reserve target share changes.

BurnEpochSet

event BurnEpochSet(uint32 duration)

Fires when the epoch length changes.

EpochRolled

event EpochRolled(uint256 start, uint256 budget)

Fires when a new burn epoch starts, with its start and budget.

Covered

event Covered(uint256 amount)

Fires when reserve USDG is sent to the pool to cover bad debt.

BuyAndBurn

event BuyAndBurn(uint256 usdgIn, uint256 stkBurned)

Fires when treasury USDG is swapped and the output is burned.

CollateralSwept

event CollateralSwept(
    address indexed token,
    uint256 amountIn,
    uint256 usdgOut
)

Fires when seized collateral is sold for USDG.

Errors

ZeroAddress

error ZeroAddress()

A constructor address was zero, or the registry has no DEX router.

NotCore

error NotCore()

Only Stockline can notify fees.

NotOwner

error NotOwner()

Only the timelock can change the target or epoch.

ZeroAmount

error ZeroAmount()

An amount was zero or nothing was available.

InvalidWad

error InvalidWad()

The reserve target share is above 1e18.

InsufficientTreasury

error InsufficientTreasury()

The burn amount exceeds the treasury.

CapExceeded

error CapExceeded()

The burn amount exceeds maxPerCall.

InvalidRoute

error InvalidRoute()

The swap route is missing, too short, or has the wrong endpoints.

NotAllowed

error NotAllowed()

The token has no allowed zap route.

InvalidEpoch

error InvalidEpoch()

The epoch length is outside 1 to 90 days.

EpochBudgetExceeded

error EpochBudgetExceeded()

The burn amount exceeds the unused budget of the current epoch.

​Write methods

​notifyInterest

​notifyLiquidationFee

​credit

​setReserveTargetPct

​setBurnEpoch

​allocate

​coverBadDebt

​buyAndBurn

​sweepCollateral

​Read methods

​reserveTarget

​unallocated

​Events

​Allocated

​Credited

​ReserveTargetPctSet

​BurnEpochSet

​EpochRolled

​Covered

​BuyAndBurn

​CollateralSwept

​Errors

​ZeroAddress

​NotCore

​NotOwner

​ZeroAmount

​InvalidWad

​InsufficientTreasury

​CapExceeded

​InvalidRoute

​NotAllowed

​InvalidEpoch

​EpochBudgetExceeded

Write methods

notifyInterest

notifyLiquidationFee

credit

setReserveTargetPct

setBurnEpoch

allocate

coverBadDebt

buyAndBurn

sweepCollateral

Read methods

reserveTarget

unallocated

Events

Allocated

Credited

ReserveTargetPctSet

BurnEpochSet

EpochRolled

Covered

BuyAndBurn

CollateralSwept

Errors

ZeroAddress

NotCore

NotOwner

ZeroAmount

InvalidWad

InsufficientTreasury

CapExceeded

InvalidRoute

NotAllowed

InvalidEpoch

EpochBudgetExceeded