THE DOCSREAD
Getting-started docs at ethereum.github.io/kohaku, the entry point for wallet teams evaluating the SDK.
|=[ DEEP DIVE :: PROTOCOL FILE 004 ]=
KOHAKU
KOHAKU · ETHEREUM FOUNDATIONThe Ethereum Foundation's reference implementation of a privacy-preserving wallet, plus the open-source SDK behind it, announced in the EF's "Commitment to Privacy" (08.10.2025), which closes with three words: privacy is normal.
EF WALLET SDK ERC-4337 POST-QUANTUM ACCOUNT OPEN SOURCE
ANNOUNCED — 08.10.2025 · ETHEREUM FOUNDATION
47
EF Privacy Cluster
people, coordinated by Igor Barinov
6
Packages in the SDK
@kohaku-eth/* on GitHub
3
Privacy protocols inside
Railgun · Tornado Cash · Privacy Pools
11.2025
Public demo
Devconnect Buenos Aires
AMBIRE
Extension forked from
built with Railgun, Helios, PSE
EF BLOG + GITHUB + ROADMAP, CROSS-CHECKED
ANNOUNCED 08.10.2025 BY ETHEREUM FOUNDATION STATUS REFERENCE IMPLEMENTATION TX ROUTING ERC-4337 MEMPOOL RPC READS HELIOS LIGHT CLIENT POST-QUANTUM ACCOUNT YES
THE STACK WALLETS BUILD ON
Privacy shouldn't be a separate app you remember to open. Kohaku packages the privacy protocols as libraries any wallet can ship.
01 Protocol library.
Railgun, Tornado Cash and Privacy Pools as importable libraries: the shielded-pool protocols become dependencies (@kohaku-eth/railgun, -/tornado-cash, -/privacy-pools) instead of bespoke one-off integrations.
02 Plugins.
A standardized plugin interface (@kohaku-eth/plugins) so a wallet adds a privacy protocol the way it adds a network: one interface, any protocol behind it.
03 Reads.
One provider abstraction (@kohaku-eth/provider) over ethers, viem, Helios and Colibri. The Helios light client verifies chain data locally, so reads stop depending on an RPC operator's word.
04 Writes.
Privacy-protocol transactions route through the ERC-4337 mempool, so users don't depend on centralized relayers. A post-quantum 4337 account (@kohaku-eth/pq-account) is in the same stack.
THE STACK
THE REFERENCE WALLET
The Kohaku extension is a browser wallet forked from Ambire and developed in collaboration with Ambire, Railgun, Helios and PSE. It was demoed publicly at Devconnect Buenos Aires in 11.2025. It exists as a working example the ecosystem can copy, with the privacy plumbing already done.
SIX PACKAGES, ONE SDK
"Privacy-first tooling for the Ethereum ecosystem" — the repo's own words.
| PACKAGE | WHAT IT IS |
|---|---|
| @kohaku-eth/railgun | Railgun shielded balances as a protocol library |
| @kohaku-eth/tornado-cash | Tornado Cash pools as a protocol library |
| @kohaku-eth/privacy-pools | Privacy Pools as a protocol library |
| @kohaku-eth/plugins | Standardized plugin interface for privacy protocols |
| @kohaku-eth/provider | Provider abstraction — ethers · viem · Helios · Colibri |
| @kohaku-eth/pq-account | Post-quantum ERC-4337 account |
Privacy Pools, Railgun, and Tornado Cash have full deep dives on this site.
TRADE OFFS
Serious infrastructure with the right architecture, at a stage worth naming precisely:
IT'S EARLY
Kohaku is a reference implementation in active development, a roadmap-stage project still short of a daily-driver wallet you'd move savings into today. The demos are real, the docs are live, and the maturity label matters.
AN SDK ISN'T PRIVACY BY ITSELF
Users get privacy once wallets ship these packages; publishing them is only step one. The bet is that standardized libraries lower the integration cost enough that privacy becomes a default wallet feature rather than a separate app. That bet still has to play out.
THE EF BUILDS THE PLUMBING
The reference extension exists to be copied, and the wallet UX will come from the ecosystem; the Ambire collaboration is the model. Scope is a feature here, but it means the polished consumer experience is someone else's roadmap.
USE IT
THE CODEBUILD
The SDK monorepo at github.com/ethereum/kohaku; the reference browser extension (Ambire fork) at github.com/ethereum/kohaku-extension.
THE ROADMAPTRACK
The public roadmap (09.10.2025) on the EF's notes instance: what's landed, what's next, and how the extension and SDK tracks fit together.
Evaluating Kohaku but not sure if it fits your product? Talk to Ben.
TALK TO BEN →THE EF PRIVACY PUSH
Kohaku is one initiative inside a coordinated effort: the EF put 47 people on privacy and said so in public.
THE PRIVACY CLUSTEREF
A 47-person cluster coordinated by Igor Barinov, announced 08.10.2025. Initiatives: Private Reads & Writes, Private Proving, Private Identities, Privacy Experience, the Institutional Privacy Task Force, and Kohaku.
PSE — SHUT DOWN 06.2026RESEARCH
Privacy Stewards of Ethereum built much of the stack Kohaku draws on (Semaphore, MACI, zkEmail, TLSNotary, the ORAM private-RPC research). The EF shut PSE down on 23.06.2026, cutting 54 roles; Kohaku itself continues at the EF, MACI moved to the community privacy-ethereum org, and the institutional work spun out as EthSystems (14.07.2026).
THE PROTOCOLS INSIDESIGNAL
Kohaku is the first core-infrastructure integration of Privacy Pools (demoed at Cypherpunk Congress, Devconnect Buenos Aires, 11.2025), and the extension is built in collaboration with Railgun. Deep dives: Privacy Pools · Railgun.