feat(incentives): add protocol fee (#1691)

**Motivation:**

We want to add a configurable protocol fee mechanism to the
RewardsCoordinator contract to enable revenue generation. This allows
reward submitters to opt into paying fees while maintaining backward
compatibility with existing integrations.

**Modifications:**

- Added protocolFee (fixed constant amount) and feeRecipient state
variables
- Implemented setOptInProtocolFee() for submitters to opt into fee
payments
- Implemented setFeeRecipient() (owner-only) to set the fee destination
address

**Result:**

Submitters can voluntarily enable protocol fees on their reward
distributions. When opted in, the fixed fee amount is deducted and sent
to the designated recipient. Existing integrations continue working
unchanged since fees are disabled by default.

Author: 0xClandestine

.gitignore

@@ -17,6 +17,7 @@ artifacts
 #Foundry files
 out
 cache
+snapshots
 
 *.DS_Store
 

script/deploy/devnet/deploy_from_scratch.s.sol

@@ -312,7 +312,8 @@ contract DeployFromScratch is Script, Test {
                 REWARDS_COORDINATOR_INIT_PAUSED_STATUS,
                 REWARDS_COORDINATOR_UPDATER,
                 REWARDS_COORDINATOR_ACTIVATION_DELAY,
-                REWARDS_COORDINATOR_GLOBAL_OPERATOR_COMMISSION_BIPS
+                REWARDS_COORDINATOR_GLOBAL_OPERATOR_COMMISSION_BIPS,
+                executorMultisig // feeRecipient
             )
         );
 

script/deploy/local/deploy_from_scratch.slashing.s.sol

@@ -219,9 +219,6 @@ contract DeployFromScratch is Script, Test {
         allocationManager = AllocationManager(
             address(new TransparentUpgradeableProxy(address(emptyContract), address(eigenLayerProxyAdmin), ""))
         );
-        allocationManagerView = AllocationManagerView(
-            address(new TransparentUpgradeableProxy(address(emptyContract), address(eigenLayerProxyAdmin), ""))
-        );
         permissionController = PermissionController(
             address(new TransparentUpgradeableProxy(address(emptyContract), address(eigenLayerProxyAdmin), ""))
         );
@@ -237,6 +234,9 @@ contract DeployFromScratch is Script, Test {
         eigenPodBeacon = new UpgradeableBeacon(address(eigenPodImplementation));
 
         // Second, deploy the *implementation* contracts, using the *proxy contracts* as inputs
+        // Deploy AllocationManagerView as a standalone implementation (not a proxy)
+        allocationManagerView =
+            new AllocationManagerView(delegation, eigenStrategy, DEALLOCATION_DELAY, ALLOCATION_CONFIGURATION_DELAY);
 
         delegationImplementation = new DelegationManager(
             strategyManager,
@@ -327,7 +327,8 @@ contract DeployFromScratch is Script, Test {
                 REWARDS_COORDINATOR_INIT_PAUSED_STATUS,
                 REWARDS_COORDINATOR_UPDATER,
                 REWARDS_COORDINATOR_ACTIVATION_DELAY,
-                REWARDS_COORDINATOR_DEFAULT_OPERATOR_SPLIT_BIPS
+                REWARDS_COORDINATOR_DEFAULT_OPERATOR_SPLIT_BIPS,
+                executorMultisig // feeRecipient
             )
         );
 

script/releases/TestUtils.sol

@@ -926,7 +926,7 @@ library TestUtils {
         RewardsCoordinator rewardsCoordinator
     ) internal {
         vm.expectRevert(errInit);
-        rewardsCoordinator.initialize(address(0), 0, address(0), 0, 0);
+        rewardsCoordinator.initialize(address(0), 0, address(0), 0, 0, address(0));
     }
 
     function validateStrategyManagerInitialized(

script/utils/ExistingDeploymentParser.sol

@@ -522,7 +522,8 @@ contract ExistingDeploymentParser is Script, Logger {
             0, // initialPausedStatus
             address(0), // rewardsUpdater
             0, // activationDelay
-            0 // defaultSplitBips
+            0, // defaultSplitBips
+            address(0) // feeRecipient
         );
         // DelegationManager
         cheats.expectRevert(bytes("Initializable: contract is already initialized"));

snapshots/Integration_ALM_Multi.json

@@ -202,8 +202,6 @@ contract EmissionsController is
                 success = _tryCallRewardsCoordinator(
                     abi.encodeCall(IRewardsCoordinator.createAVSRewardsSubmission, (rewardsSubmissions))
                 );
-            } else {
-                revert InvalidDistributionType(); // Only reachable if the distribution type is `Disabled`.
             }
         } else {
             (success,) =

src/contracts/core/EmissionsController.sol

@@ -48,6 +48,9 @@ abstract contract RewardsCoordinatorStorage is IRewardsCoordinator {
     /// @notice Canonical, virtual beacon chain ETH strategy
     IStrategy public constant beaconChainETHStrategy = IStrategy(0xbeaC0eeEeeeeEEeEeEEEEeeEEeEeeeEeeEEBEaC0);
 
+    /// @notice Protocol fee percentage in basis points (20%).
+    uint16 internal constant PROTOCOL_FEE_BIPS = 2000;
+
     // Immutables
 
     /// @notice The DelegationManager contract for EigenLayer
@@ -136,6 +139,12 @@ abstract contract RewardsCoordinatorStorage is IRewardsCoordinator {
     /// @notice Returns whether a `hash` is a `valid` total stake rewards submission hash for a given `avs`.
     mapping(address avs => mapping(bytes32 hash => bool valid)) public isTotalStakeRewardsSubmissionHash;
 
+    /// @notice Returns whether a `submitter` is opted in for protocol fees.
+    mapping(address submitter => bool isOptedIn) public isOptedInForProtocolFee;
+
+    /// @notice The address that receives optional protocol fees
+    address public feeRecipient;
+
     // Construction
     constructor(
         IDelegationManager _delegationManager,
@@ -164,5 +173,5 @@ abstract contract RewardsCoordinatorStorage is IRewardsCoordinator {
     /// @dev This empty reserved space is put in place to allow future versions to add new
     /// variables without shifting down storage in the inheritance chain.
     /// See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
-    uint256[33] private __gap;
+    uint256[31] private __gap;
 }

src/contracts/core/RewardsCoordinator.sol

@@ -414,6 +414,17 @@ interface IRewardsCoordinatorEvents is IRewardsCoordinatorTypes {
         IERC20 token,
         uint256 claimedAmount
     );
+
+    /// @notice Emitted when the fee recipient is set.
+    /// @param oldFeeRecipient The old fee recipient
+    /// @param newFeeRecipient The new fee recipient
+    event FeeRecipientSet(address indexed oldFeeRecipient, address indexed newFeeRecipient);
+
+    /// @notice Emitted when the opt in for protocol fee is set.
+    /// @param submitter The address of the submitter
+    /// @param oldValue The old value of the opt in for protocol fee
+    /// @param newValue The new value of the opt in for protocol fee
+    event OptInForProtocolFeeSet(address indexed submitter, bool indexed oldValue, bool indexed newValue);
 }
 
 /// @title Interface for the `IRewardsCoordinator` contract.
@@ -431,7 +442,8 @@ interface IRewardsCoordinator is IRewardsCoordinatorErrors, IRewardsCoordinatorE
         uint256 initialPausedStatus,
         address _rewardsUpdater,
         uint32 _activationDelay,
-        uint16 _defaultSplitBips
+        uint16 _defaultSplitBips,
+        address _feeRecipient
     ) external;
 
     /// @notice Creates a new rewards submission on behalf of an AVS, to be split amongst the
@@ -606,6 +618,13 @@ interface IRewardsCoordinator is IRewardsCoordinatorErrors, IRewardsCoordinatorE
         uint16 split
     ) external;
 
+    /// @notice Sets the fee recipient address which receives optional protocol fees
+    /// @dev Only callable by the contract owner
+    /// @param _feeRecipient The address of the new fee recipient
+    function setFeeRecipient(
+        address _feeRecipient
+    ) external;
+
     /// @notice Sets the split for a specific operator for a specific avs
     /// @param operator The operator who is setting the split
     /// @param avs The avs for which the split is being set by the operator
@@ -643,6 +662,15 @@ interface IRewardsCoordinator is IRewardsCoordinatorErrors, IRewardsCoordinatorE
         uint16 split
     ) external;
 
+    /// @notice Sets whether the submitter wants to pay the protocol fee on their rewards submissions.
+    /// @dev Submitters must opt-in to pay the protocol fee to be eligible for rewards.
+    /// @param submitter The address of the submitter that wants to opt-in or out of the protocol fee.
+    /// @param optInForProtocolFee Whether the submitter wants to pay the protocol fee.
+    function setOptInForProtocolFee(
+        address submitter,
+        bool optInForProtocolFee
+    ) external;
+
     /// @notice Sets the permissioned `rewardsUpdater` address which can post new roots
     /// @dev Only callable by the contract owner
     /// @param _rewardsUpdater The address of the new rewardsUpdater