Fault proofs on Base Sepolia (Testnet)
Scheduled Maintenance Report for Base
Completed
The scheduled maintenance has been completed.
Posted Jul 23, 2024 - 16:58 UTC
In progress
Scheduled maintenance is currently in progress. We will provide updates as necessary.
Posted Jul 23, 2024 - 16:00 UTC
Scheduled
Fault proofs are a critical implementation in Base’s path towards decentralization. They enable a more decentralized approach to validating L2 state and pave the way for more community participation.

They improve decentralization with two important capabilities:

1. Permissionless output proposals: In an L2 without fault proofs, only the centralized proposer can create and submit output roots about the state of the L2. Now, with fault proofs, anyone can make claims about Base's current state instead of relying on a central party.

2. Permissionless challenges to output proposals: If someone makes a faulty or fraudulent claim, anyone can challenge it.

These changes allow anyone to withdraw funds from Base to L1 without having to rely on centralized actors. Below is all the information you need to prepare for fault proofs on Base Sepolia (Testnet).

### What’s Changing for Testnet Withdrawals:

- Withdrawals will involve proving and finalizing based on the fault proof system.
- Withdrawals will no longer be instantaneous: they will take at least seven days to finalize but can take longer depending on the outcome of the corresponding dispute game.
- The 'DisputeGameFactory' will replace the 'L2OutputOracle' as the new contract for proposing output root statements. This change is part of the broader shift towards the fault proofing system, which is expected to enhance the security and reliability of the platform.

### If You Are Withdrawing Testnet Funds from L2 to L1:

- Withdrawals before the upgrade will be processed instantaneously.
- Withdrawals during or after the fault proofs upgrade for Base Sepolia will take at least seven days to complete.
- If your withdrawal of testnet funds from Base Sepolia to Ethereum Sepolia coincides with the upgrade, you will be required to resubmit your withdrawal.

### IMPORTANT: For Teams Operating a Bridge on Base Sepolia:

- Please provide your users with a notice on your UI to inform them that fault proofs will be enabled for Base Sepolia.
- Ensure it’s clear to your users that testnet withdrawals will now take at least seven days.
- Assess and update your bridging logic, and make sure the new L1 contracts are being used.

Fault proof contract upgrades will be completed atomically, meaning all affected L1 contracts will be upgraded in a single transaction. No action will be required from node operators.

If you have any questions, please don't hesitate to reach out in the #developer-support channel in the Base Discord, where we'll be happy to help you: https://base.org/discord
Posted Jul 22, 2024 - 23:04 UTC
This scheduled maintenance affected: Testnet (Withdrawals) and Bridge (Testnet).