EY upgrades Nightfall, a zero-knowledge roll-up enabling private transactions on the Ethereum blockchain

• The new source code for Nightfall, renamed Nightfall_4, replaces the prior version.
• This update provides the near-instant finality of layer-1 blockchain transactions without the need for a challenge period.
• Nightfall enables enterprises to orchestrate private transactions efficiently on Ethereum without compromising its benefits of transparency, data immutability and security.

LONDON, April 3, 2025 /PRNewswire/ -- The EY organization today announces it has updated the public domain source code for Nightfall¹, a layer-2 roll-up that enables private transactions on the public Ethereum blockchain and the development of privacy-focused enterprise blockchain solutions.

This updated version of Nightfall replaces the optimistic roll-up with a zero-knowledge version – enabling the near-instant finality of transactions on the blockchain without the need for a challenge period. Using Nightfall, enterprises can orchestrate private transactions efficiently on the Ethereum mainnet, without compromising the transparency, data immutability and security that Ethereum provides.

The replacement of a cryptoeconomic approach with a cryptographic approach simplifies Nightfall's architecture because there is no need to accommodate challenging incorrect blocks, nor to provide liquidity services to avoid users having to wait out the challenge period to get their tokens. As soon as a Nightfall block is added to the chain, the transactions it contains are as final as any other blockchain transaction.

This simplifies the operating requirements for Nightfall, making privacy technology more accessible for enterprise users. Nightfall's other features, such as access provision through x509 enterprise identity certificates and the enhanced scalability with privacy, have all been retained.

The source code for Nightfall, renamed Nightfall_4, and supporting tools are in the public domain and are available on Github. Nightfall remains in the public domain to facilitate the adoption of privacy-focused enterprise solutions among companies seeking to enter Ethereum and conduct meaningful business on the network.

The EY organization first contributed Nightfall to the public domain in 2019 as a set of protocols for enabling private transactions on the Ethereum blockchain, and Nightfall_4 is the fourth major update to the software. EY core software and service offerings in the global blockchain market, such as, EY OpsChain, use Nightfall, and both are delivered through EY Blockchain's SaaS platform, Blockchain.ey.com.

Paul Brody, EY Global Blockchain Leader, says:

"This update to version 4 represents a major update to Nightfall, providing the same privacy and scaling that version 3 enabled, but now with near-instant finality and a simplified architecture. We believe we will see accelerating adoption of this technology in the coming year by enterprise users."

For more information visit Blockchain.ey.com.

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¹ Nightfall is an internal project name at the EY organization for code related to privacy on a blockchain. This code is not owned by the EY organization and the EY organization provides no warranty and disclaims any and all liability for use of this code. Users must conduct their own diligence with respect to use for their purposes, and any and all usage is on an as-is basis and at your own risk.