Ethereum Kohaku Privacy Framework

Kohaku: Rebuilding Ethereum’s Privacy Foundation with Open Source Frameworks

At the latest Devcon, Ethereum co-founder Vitalik Buterin announced the open-source privacy toolkit Kohaku, developed jointly by the Ethereum Foundation and several core teams. Kohaku aims to establish a scalable modular architecture that supports privacy operations on Layer 1, allowing users to maintain control over their data permissions while enjoying decentralized transparency.

Kohaku’s module includes mixnets integration, ZK verification frontend components, and a full-link privacy transaction process. The framework has been open-sourced on GitHub, with the first batch of tools including Railgun and Privacy Pools. Among them, Privacy Pools use an “association list” mechanism, allowing users to maintain privacy while having proof of innocence, successfully achieving a balance between privacy and compliance.

Technical Demonstration: Privacy Wallet Officially Launched

In November 2025, the Kohaku team showcased the first prototype of a privacy wallet, demonstrating how to convert public assets into concealed funds through Railgun while retaining proof of legality. In the future, the team will integrate with commonly used wallets such as MetaMask, Rainbow, and Rabby to implement preset privacy transaction modes, making privacy a standard rather than an option.

Vitalik stated: “True freedom comes from privacy; blockchains should allow users to self-determine, rather than being forced to disclose every action.” This statement also embodies the core philosophy of Ethereum’s privacy upgrade.

Privacy Cluster: Focused on Layer 1 Confidential Protocols

To support the development of Kohaku, the Ethereum Foundation has established a new department called Privacy Cluster, composed of 47 engineers and cryptography experts, responsible for the R&D of L1 privacy standards, zero-knowledge consensus, confidential transactions, and security audits. The team’s goal is to embed privacy into the Ethereum underlying protocol, making it a native attribute of the protocol rather than an additional feature.

At the same time, the team formerly known as “Privacy & Scaling Explorations” has been renamed Privacy Stewards of Ethereum, symbolizing a shift in focus from technical exploration to practical implementation, covering private governance, confidential voting, and DeFi privacy mechanisms, gradually transforming theory into application standards.

Rebalancing Privacy and Transparency

The privacy reform of Ethereum is not just a technological update, but a transformation of ecological philosophy. Kohaku represents a new concept: transparency does not equal exposure, but rather empowers users with choices. Through zero-knowledge tools and compliance-oriented frameworks, Ethereum is moving from a “completely public ledger” to a “controllable and transparent trust system,” making blockchain a public utility that is free, secure, and compliant with regulations.

Summary

The launch of Kohaku symbolizes the formal establishment of privacy infrastructure on Ethereum. This suite combines open-source collaboration, ZK technology, and governance mechanisms, allowing privacy to be integrated into the mainnet design, enabling Web3 users to achieve a balance between security and auditability. When privacy is transformed into preset mechanisms, Ethereum will evolve from a decentralized computing platform into a truly “user-centric” global protocol network.