Ethereum researchers are exploring how to deploy a new protocol introduced earlier this year that could greatly enhance on-chain privacy using zero-knowledge proofs.
On Monday, Ethereum developer Artem Chystiakov shared an update on the Ethereum community forum titled “Zero Knowledge Secret Santa (ZKSS)”, outlining a three-step algorithm modeled after the classic Secret Santa game. The idea was first presented in a January arXiv paper.
Secret Santa, traditionally played around Christmas, involves participants anonymously exchanging gifts. Each person gives a present to someone in the group and receives one in return—without ever knowing who their gift came from.
The challenge on Ethereum
According to Chystiakov, running a Secret Santa game on Ethereum faces three major obstacles:
- Transparency – Everything on Ethereum is public, so sender–receiver relationships must be hidden.
- Lack of native randomness – Participants must generate randomness in a way that can’t be manipulated.
- Fairness – The system must prevent double participation and stop players from assigning gifts to themselves.
Broader applications for Ethereum privacy
Privacy has become a major focus as crypto tools merge with traditional finance. A protocol like ZKSS could be adapted for:
- Anonymous voting or governance in DAOs where users prove membership and cast a single vote without revealing their identity.
- Whistleblower systems, enabling authorized employees to submit reports privately.
- Private airdrops or token allocations, allowing distribution without exposing recipients.
When asked about open-source code or deployment timelines, Chystiakov said the team is actively working on it.
How ZK Secret Santa works
The proof-of-concept Solidity implementation uses zero-knowledge proofs to define sender–recipient assignments while keeping the giver’s identity secret. A transaction relayer submits the transactions on behalf of participants, ensuring their addresses remain concealed.
ZK-proofs let someone prove they know certain information without revealing the information itself—making them ideal for privacy-preserving systems like ZKSS.
To join the game, users first register their Ethereum addresses in a smart contract, creating a complete participant list. Each person also commits to a specific digital signature, which prevents cheating by ensuring no one can join multiple times under different identities.
Next, every participant privately contributes a random number to a shared pool via a transaction relayer, keeping the source of each number hidden. These random values enable recipients to encrypt their delivery information so that only their assigned “Secret Santa” can decrypt it.
In the final step, each participant selects one of the random numbers from the shared pool. That selection determines their recipient, revealing only the identity of the person they are gifting to—without revealing who will gift to them.
