Approve the Nova Fee Sweep Action

Abstract

The Nova Fee Sweep action applies to historical Nova transaction fees currently held in the L1TimelockAlias; these fees will be swept into the DAO Treasury with the use of the modernized fee collection infrastructure outlined in the Nova Fee Router Proposal. The full balance of ETH–currently 1,885 ETH–will be transferred to the DAO Treasury on Arbitrum One using established smart contract infrastructure.

There will be an upcoming AIP which combines both the Timeboost AIP and the Nova Fee Sweep action AIP into a single proposal for an on-chain vote on Tally. If the on-chain vote on Tally passes successfully, Timeboost will be enabled on Arbitrum One and Arbitrum Nova and the Nova Fee Sweep action will be executed. This temperature check serves as a way for the DAO to explicitly approve for the fees from the historical L1TimelockAlias to the ChildToParentRouter.

Motivation

Historically, Nova transaction fees accumulated to the L1TimelockAlias address, which required a lengthy constitutional proposal process for the ArbitrumDAO to access or spend. The successful passing of the Nova Fee Router proposal redirected these fees to a system of "fee routers" that automatically transfers funds to the ArbitrumDAO treasury, reducing quorum requirements, reducing delays, and simplifying accounting by consolidating funds directly in the treasury. As of 28 August 2024, Nova transaction fees began accumulating to a series of RewardDistributor contracts as outlined in the Nova Fee Router proposal, streamlining the revenue collection process for the DAO.

However, transaction fees that accumulated to the L1TimelockAlias before the Nova Fee Router change went into effect remain in the L1TimelockAlias, totalling 1,885.79 ETH. This proposal intends to sweep these historical Nova transaction fees from the legacy L1TimelockAlias address into the new fee collection system. This will be a one-time task because funds collected after 28 August 2024 have been, and will continue to be, automatically forwarded through the new fee collection system to the ArbitrumDAO treasury.

Key Terms

L1TimelockAlias: address that historically accumulated Nova transaction fees but was replaced by RewardDistributor contracts as a part of the Nova Fee Router Proposal to upgrade the fee collection infrastructure; historical fees held by this address are the subject of this proposal.

ChildToParentRouter: smart contract that, when called, creates an L2-to-L1 message which sends the contract’s full ETH balance; once the message is executed, the ETH is transferred to a ParentToChildRouter smart contract on L1

ParentToChildRouter: smart contract that, when called, creates a retryable ticket which transfers the contract’s full ETH balance from L1 to the DAO Treasury on Arbitrum One

The full script for executing the Nova Fee Sweep can be found here: Standalone Nova Fee Sweep Proposal #303

Steps to Implement

The script will be included alongside the onchain AIP which proposes for the adoption of Timeboost on Tally. Since both changes are bundled into one onchain AIP, this temperature check serves as a way for the DAO to explicitly approve for the fees from the historical L1TimelockAlias to the ChildToParentRouter.

Once transaction fees are received by the ChildToParentRouter, the automated fee collection process will be activated, forwarding fees to the ParentToChildRouter on L1 and eventually to the DAO Treasury on Arbitrum One; complete implementation details for this automated fee routing can be found in the preceding Tally proposal. Please note that Reward Distributor contracts are irrelevant for this particular action as historical fees from the L1TimelockAlias will be transferred directly to the ChildToParentRouter.

Resources and Timelines:

Timeboost + Nova Fee Sweep AIP forum post Nova Fee Sweep Snapshot: 30 Jan - 6 Feb

The Arbitrum Foundation will communicate a tentative date for the creation of the onchain AIP in the near future.