Ink Implements Permissionless Fault Proofs

Ink, the Ethereum scaling layer incubated by crypto exchange Kraken, is implementing permissionless fault proofs on Thursday, according to network creator Andrew Koller in an interview with The Block.

This move represents the latest technical advancement for Ink, which has experienced rapid development since its early launch in December.

Notably, Ink is the first Superchain network to incorporate multiple challengers since Optimism tested this capability on the OP Mainnet late last year. At launch, both the smart contract automation protocol Gelato and Kraken will operate Ink challengers, an onchain tool that allows anyone to challenge the validity of a transaction.

Ink signifies a new approach at Kraken, one of the oldest exchanges established in 2011. After hiring Arjun Sethi as co-CEO, the company has reduced staff and bureaucratic overhead to operate more like a startup.

Last week, Ink also became the testing ground for Tether’s new multi-chain tokenized dollar, USDT0. Koller expressed hopes that their rapid progress alongside Optimism will set a new standard.

What are Fault Proofs?

Fault proofs, introduced to the OP Stack in June 2024, are crucial for Optimistic rollups, a scaling solution that assumes transactions are valid unless proven otherwise. Users can submit proofs that challenge the state of an L2 like Ink and are rewarded with a portion of the disputed funds if they accurately identify a fraudulent or erroneous transaction.

At launch, Kraken seeded its challenger with around 49 ETH (approximately $156,000) to ensure sufficient ETH for state changes. Optimism typically suggests seed amounts of about 14 ETH. Koller stated, “We’ll flip the switch, and then anyone with ETH can stake it in this challenger, enabling decentralized operations.”

Code is Law?

Having multiple challengers is essential for maintaining “credible neutrality,” a foundational principle of Ethereum where no party should unfairly influence the chain. Currently, most Superchain networks use centralized challengers, allowing them unilateral control over state changes.

Fault proofs can reverse any transaction on an L2, with ongoing discussions about the proper terminology of “fault proofs” versus “fraud proofs,” as virtually any transaction could be challenged. Koller stated, “If there’s consensus and they want to act, that’s the technology’s purpose.” He underscored that Ink could face criticism as a corporate chain with a centralized sequencer, but emphasized their steps towards decentralization.

He expressed a desire for the crypto community to hold all parties accountable and foster a collaborative environment.

Rolling Out on a Rollup

Fault proofs are now standard on OP chains. Unichain prioritized implementing them from its mainnet launch, and Coinbase’s Base network rolled them out last October.

Koller mentioned that around 10 people, including engineers from Kraken, Gelato, and Optimism’s fault proof team, were involved in launching permissionless fault proofs on Ink. He noted that their fast pace initially prevented the inclusion of fraud proofs but they prioritized security and took time to ensure everything was secure.

“We like to move fast. We like to be secure with it though,” Koller concluded.