Managed credit vault

Fuel Credit V9 is the legacy managed ecosystem credit vault. V10 preserves its role and capital separation while adding two-step ownership and floor-rounded pro-rata maturity settlement. V9 positions keep their original all-or-nothing terms; neither version has a grace or post-maturity cure period.

Authority model

• The owner controls ownership, oracle rotation, pool withdrawals, manager proposals, and strategy approval.
• The manager may deploy free capital to approved strategies and record bounded strategy write-downs.
• A manager change is two-step: the owner proposes a nonzero identity and only that pending identity can accept.
• An approved strategy identity returns its own deployed assets directly. Principal reduces its exposure; any excess is recorded as realized yield.

The manager cannot approve strategies or change ownership. A strategy cannot be disabled while it has tracked exposure. These controls improve auditability but do not make a strategy trustless.

Capital accounting

capital_accounting() returns three asset-specific AssetLiability views plus the outstanding USDC loan receivable. Each view reports:

• onchain balance;
• borrower collateral owed;
• free onchain capital;
• strategy exposure;
• realized strategy yield; and
• realized strategy loss.

Borrower FUEL and stFUEL collateral owed is a liability and is excluded from deployable and withdrawable balances. Strategy exposure is deployed capital, not a liability. USDC deployed to a strategy immediately reduces liquidity available for new loans.

strategy_state(identity) separately exposes whether a strategy is known/allowed and its USDC, FUEL, and stFUEL exposure.

Strategy lifecycle

1. Owner calls set_strategy(strategy, true).
2. Manager calls deploy_to_strategy(strategy, asset, amount) using only free onchain capital.
3. The same strategy identity returns assets through payable return_from_strategy().
4. If capital is unrecoverable, the manager calls write_down_strategy(strategy, asset, amount), bounded by recorded exposure.
5. Once exposure reaches zero, the owner may disable the strategy.

Every manager handoff, permission change, deployment, return/yield, and write-down emits an event. Contract reads remain authoritative.

Liquidity and borrower safety

• USDC funds borrower principal.
• FUEL and stFUEL collateral remain locked until the existing repayment/maturity rules release or default them.
• Strategy execution cannot deploy locked borrower collateral.
• Repayment, collateral claims, and permissionless default finalization retain the V8 behavior and remain oracle-independent.

Strategy use introduces venue, custody, counterparty, liquidity, manager, and loss risk. Operators must maintain buffers and reconcile strategy positions against contract exposure. See Risks and assumptions, Architecture, and Deployments.