Not only open source, also deployed as a smart contact on the Ethereum blockchain.
It’s possible to deploy a smart contract with no way to modify it, meaning it’s literally impossible to shutdown (without shutting down the entire network). This is rare, most dev teams retain admin keys and compose the smart contact components from additional layers of abstraction to allow for updates. But those admin keys typically also allow the possessor to abscond with all funds locked in the contracts (a rugpull).
My understanding is Tornado Cash eventually added a limited form of KYC to the frontend web UI. That’s simply a convenient interface to use the smart contract though, and it’s possible to interact with the smart contact directly (where there’s no KYC).
It’s possible to deploy a smart contract with no way to modify it, meaning it’s literally impossible to shutdown (without shutting down the entire network). This is rare, most dev teams retain admin keys and compose the smart contact components from additional layers of abstraction to allow for updates. But those admin keys typically also allow the possessor to abscond with all funds locked in the contracts (a rugpull).
My understanding is Tornado Cash eventually added a limited form of KYC to the frontend web UI. That’s simply a convenient interface to use the smart contract though, and it’s possible to interact with the smart contact directly (where there’s no KYC).