Proposal: Polygon zkEVM Improvement Proposal: Integration of zk-SNARKs for Enhanced Privacy and Scalability

Title: Polygon zkEVM Improvement Proposal: Integration of zk-SNARKs for Enhanced Privacy and Scalability
Authors: Pintea Tudor

Type: Protocol Upgrade

Table of Contents:

  • Abstract
  • Motivation
  • Definitions
  • Specification
  • Backward Compatibility
  • Security Considerations
  • Copyright


This proposal suggests a protocol upgrade for the Polygon zkEVM to integrate zk-SNARKs (Zero-Knowledge Succinct Non-Interactive Argument of Knowledge) to enhance transaction privacy and scalability. The upgrade involves the implementation of a new zk-SNARK module that will allow users to execute private transactions that are verifiable by the network without revealing any transaction-specific information.


The current state of blockchain technology on Ethereum and its Layer 2 solutions, including Polygon zkEVM, offers limited privacy options for users. Transactions are transparent, which can be a concern for both individuals and enterprises that require confidentiality. By integrating zk-SNARKs, Polygon zkEVM can offer enhanced privacy, enabling users to transact without exposing sensitive information, while also improving scalability through efficient proof verification processes.


  • zk-SNARKs: A form of zero-knowledge proof technology that allows one party to prove to another that a statement is true without revealing any information beyond the validity of the statement itself.
  • Private Transaction: A type of transaction where the details (such as sender, receiver, and amount) are hidden from the public but can be verified as valid by the network.
  • zkEVM: A Layer 2 scaling solution for Ethereum that aims to provide scalability and privacy while maintaining compatibility with Ethereum’s existing ecosystem.


  • zk-SNARK Module: Develop and integrate a zk-SNARK module within the Polygon zkEVM infrastructure to process private transactions.
  • New Transaction Type: Introduce a new transaction type, zkPrivateTransaction, which utilizes zk-SNARKs to conceal transaction details while still ensuring they are valid and final.
  • Gas Fees: Due to the computational complexity of zk-SNARKs, zkPrivateTransaction will incur higher gas fees compared to standard transactions.
  • Opt-in Privacy: Users will have the option to choose between standard transactions and zkPrivateTransaction based on their privacy needs.

Backward Compatibility

The integration of zk-SNARKs will be implemented as an additional feature within the existing Polygon zkEVM framework. This ensures that the upgrade is backward compatible with current contracts and transactions.

Security Considerations

The introduction of zk-SNARKs must be handled with rigorous security measures, including:

  • Comprehensive auditing of the new zk-SNARK module to ensure it does not introduce vulnerabilities.
  • A phased rollout, starting with a testnet deployment, to monitor the performance and security implications before mainnet release.


This document is placed in the public domain under CC0 1.0 Universal.

By adopting this improvement proposal, Polygon zkEVM will significantly enhance its privacy features and scalability, positioning itself as a leading Layer 2 solution that caters to the evolving needs of the Ethereum ecosystem. The integration of zk-SNARKs will provide users with the option to execute private transactions, thereby expanding the use cases and appeal of the Polygon network.