In February 2024, Polygon zkEVM achieved a significant milestone with the deployment of the Etrog upgrade on its mainnet. This advancement is pivotal for developers and engineers, as it enhances the network’s compatibility with Ethereum, streamlining the development and deployment of decentralized applications (dApps).
The Etrog upgrade introduces several key features:
- Support for Additional Precompiled Contracts: Including `ecAdd`, `ecMul`, `ecPairing`, `Sha256`, and `modexp`, facilitating the deployment of Ethereum-compatible code without modifications.
- Restructured Contract Architecture: Implementing the `RollupManager` contract to manage multiple Layer 2 networks, enabling asset interoperability through the Unified Bridge.
- Optimized Block Production and Packaging: Transitioning to a fixed-time block production model, allowing each block to contain multiple transactions, improving throughput and efficiency.
For developers and engineers, understanding the technical aspects of the Etrog upgrade is crucial for leveraging its full potential. This article delves into the details of the Etrog upgrade, providing insights into its features and implications for the development and deployment of dApps on the Polygon zkEVM network.
What Is the Etrog Upgrade?
The Etrog upgrade, deployed on Polygon zkEVM’s mainnet on February 13, 2024, represents a significant evolution in Ethereum Layer 2 scaling. Named after a citron fruit, the upgrade enhances zkEVM’s compatibility with Ethereum, streamlining the development and deployment of decentralized applications (dApps).
Transition from Dragonfruit to Etrog
Prior to Etrog, Polygon zkEVM operated on the Dragonfruit upgrade, which, while an improvement over earlier versions, had limitations. Dragonfruit’s architecture, where each Layer 2 (L2) block contained a single transaction, led to inefficiencies. This design resulted in bloated databases and lacked granularity in timestamps, causing issues for dApps relying on precise timing.
Etrog addresses these challenges by allowing multiple transactions per block and assigning unique timestamps to each block within a batch. This change not only reduces database bloat but also ensures accurate timing for dApps, enhancing their functionality and user experience.
Key Features of the Etrog Upgrade
1. Precompiled Smart Contracts
Etrog introduces support for additional precompiled smart contracts, including `ecAdd`, `ecMul`, `ecPairing`, `Sha256`, and `modexp`. These additions bring Polygon zkEVM closer to achieving Type 2 ZK-EVM status, as defined by Ethereum co-founder Vitalik Buterin. This enhancement allows developers to deploy their Ethereum-compatible code on Polygon zkEVM without modifications, simplifying the development process and broadening the scope of dApp deployment.
2. Optimized Block Production
The upgrade transitions to a fixed-time block production model, enabling each block to contain multiple transactions. This approach improves throughput and efficiency, aligning more closely with Ethereum’s block production model and enhancing compatibility with existing dApps.
3. Enhanced Contract Architecture
Etrog restructures the contract architecture by introducing the `RollupManager` contract. This contract manages multiple Layer 2 networks, facilitating asset interoperability through the Unified Bridge. The new architecture lays the foundation for future developments in the Polygon Chain Development Kit (CDK) ecosystem, including features like AggLayer.
4. Improved Node Synchronization
The upgrade enhances the synchronization logic by splitting Layer 1 and Layer 2 data synchronization into separate threads. This modification addresses delays in data synchronization, improving the efficiency of Layer 1 data synchronization and ensuring timely updates across the network.
Mainnet Launch Schedule
The Etrog upgrade for Polygon zkEVM was officially deployed to the mainnet on February 13, 2024, following a 10-day timelock initiated on January 27, 2024. This structured approach ensured transparency and allowed for community review before the upgrade was finalized.
Timelock and Upgrade Process
The 10-day timelock served as a precautionary measure, providing a window for the community and developers to assess the proposed changes and raise any concerns. During this period, the upgrade proposal was made publicly available, and the necessary signatures were collected to authorize the deployment. The upgrade was then executed, bringing the Etrog enhancements to the mainnet.
Testnet Access: Cardona
Prior to the mainnet deployment, the Etrog upgrade was made available on the Cardona testnet, which is anchored to the Sepolia testnet. This provided developers with an opportunity to test and familiarize themselves with the new features and changes introduced by the upgrade. Developers could connect their wallets to the Cardona testnet using the following details:
- Network Name: Polygon zkEVM Cardona Testnet
- Bridge UI: [https://bridge-ui.cardona.zkevm-rpc.com](https://bridge-ui.cardona.zkevm-rpc.com)
- New RPC URL: [https://rpc.cardona.zkevm-rpc.com](https://rpc.cardona.zkevm-rpc.com)
- Chain ID: 2442
- Currency Symbol: ETH
- Explorer: [https://cardona-zkevm.polygonscan.com/](https://cardona-zkevm.polygonscan.com/)
This testnet environment allowed developers to ensure compatibility and smooth operation of their decentralized applications (dApps) with the new Etrog features before the mainnet launch.
Impact on Developers and Users
For developers, the mainnet deployment of the Etrog upgrade meant that they could begin utilizing the enhanced features and improvements in their live applications. The support for additional precompiled contracts and the optimized block production model offered new capabilities and efficiencies. Importantly, end-users experienced no disruptions; the upgrade was designed to be seamless, ensuring that applications continued to function as expected without requiring any changes on their part.
In summary, the structured and transparent deployment of the Etrog upgrade, coupled with the availability of the Cardona testnet, provided a robust framework for developers to transition smoothly to the enhanced Polygon zkEVM platform. The mainnet launch marked a significant step forward in the evolution of Ethereum Layer 2 scaling solutions, offering improved performance and greater compatibility for decentralized applications.
Technical Enhancements in Etrog
The Etrog upgrade introduces several technical enhancements to Polygon zkEVM, aimed at improving scalability, compatibility, and developer experience. Here’s a detailed breakdown of these improvements:
1. EVM Equivalence and Precompiled Contracts
Etrog enhances Ethereum compatibility by introducing support for additional precompiled contracts, including `ecAdd`, `ecMul`, `ecPairing`, `Sha256`, and `modexp`. These additions bring Polygon zkEVM closer to achieving Type 2 ZK-EVM status, as defined by Ethereum co-founder Vitalik Buterin. This advancement means that developers can deploy their Ethereum-compatible code on Polygon zkEVM without modifications, simplifying the development process and broadening the scope of dApp deployment.
The support for additional precompiled contracts enhances compatibility with Ethereum’s EVM, allowing developers to utilize familiar tools and libraries.
2. Optimized Block Production and Packaging
The upgrade transitions to a fixed-time block production model, enabling each block to contain multiple transactions. This approach improves throughput and efficiency, aligning more closely with Ethereum’s block production model and enhancing compatibility with existing dApps.
3. Enhanced Contract Architecture
Etrog restructures the contract architecture by introducing the `RollupManager` contract. This contract manages multiple Layer 2 networks, facilitating asset interoperability through the Unified Bridge. The new architecture lays the foundation for future developments in the Polygon Chain Development Kit (CDK) ecosystem, including features like AggLayer.
4. Improved Node Synchronization
The upgrade enhances the synchronization logic by splitting Layer 1 and Layer 2 data synchronization into separate threads. This modification addresses delays in data synchronization, improving the efficiency of Layer 1 data synchronization and ensuring timely updates across the network.
Implications for Developers
The Etrog upgrade introduces several enhancements to Polygon zkEVM, significantly impacting developers building and deploying decentralized applications (dApps). Here’s a detailed breakdown of these implications:
1. Compatibility with Ethereum Tools
The Etrog upgrade brings Polygon zkEVM closer to achieving Type 2 ZK-EVM status, as defined by Ethereum co-founder Vitalik Buterin. This advancement means that developers can deploy their Ethereum-compatible code on Polygon zkEVM without modifications, simplifying the development process and broadening the scope of dApp deployment.
The support for additional precompiled contracts, such as `ecAdd`, `ecMul`, `ecPairing`, `Sha256`, and `modexp`, enhances compatibility with Ethereum’s EVM, allowing developers to utilize familiar tools and libraries.
2. Deployment Considerations
With the Etrog upgrade, developers can deploy their dApps on Polygon zkEVM without the need for significant modifications. The enhanced compatibility ensures that existing Ethereum-based applications can operate seamlessly on the upgraded network.
However, developers should be aware of the changes in the contract architecture, particularly the introduction of the `RollupManager` contract. This restructuring may require updates to deployment scripts and configurations to align with the new architecture.
3. Performance Improvements
The Etrog upgrade introduces a fixed-time block production model, allowing each block to contain multiple transactions. This approach improves throughput and efficiency, aligning more closely with Ethereum’s block production model and enhancing compatibility with existing dApps.
Additionally, the introduction of the `cdk-erigon` RPC node offers significant scalability improvements, including increased throughput and reduced synchronization times. These enhancements contribute to a more robust and scalable development environment, facilitating the creation of sophisticated decentralized applications.
4. Developer Tools and Resources
To assist developers in transitioning to the Etrog upgrade, Polygon provides comprehensive documentation and resources. The official Polygon Knowledge Layer offers detailed information on the technical aspects of the upgrade, including changes in zkEVM architecture and transaction processing.
Additionally, developers can access the latest versions of the Node and Prover/Executor from the official GitHub repositories:
- Node: v0.5.8 / v0.5.7
- Prover/Executor: v4.0.8
These resources provide the necessary tools and information to effectively integrate the Etrog enhancements into dApp development workflows.
5. Community Support and Collaboration
Polygon fosters a vibrant developer community through various channels, including Discord and the Polygon R&D Discord. These platforms offer opportunities for developers to collaborate, share insights, and seek assistance regarding the Etrog upgrade and other Polygon zkEVM developments.
Engaging with the community can provide valuable support and facilitate knowledge sharing, ensuring a smooth transition to the upgraded network.
Infrastructure and Node Updates
The Etrog upgrade introduces several changes to the infrastructure and node architecture of Polygon zkEVM. These modifications aim to enhance scalability, security, and developer experience. Here’s a detailed breakdown of the key updates:
1. Node and Prover Versions
To ensure compatibility with the Etrog upgrade, participants in the network must update to the latest versions of the node and prover:
- Node: v0.5.8 / v0.5.7
- Prover/Executor: v4.0.8
These updates incorporate the necessary changes to support the new features introduced by the Etrog upgrade, including multi-transaction blocks and enhanced timestamp granularity.
2. RPC Node Enhancements
The introduction of the cdk-erigon RPC node offers significant scalability improvements. This new node implementation provides:
- Increased Throughput: Enhanced capacity to handle a higher volume of transactions and requests.
- Reduced Synchronization Times: Faster synchronization with the network, ensuring up-to-date data access.
These enhancements contribute to a more robust and scalable infrastructure, facilitating the development and deployment of decentralized applications on Polygon zkEVM.
3. Running a Permissionless Node
Developers and infrastructure providers interested in contributing to the network can set up a permissionless node. Running a node involves:
- Setting Up the Node: Deploying the necessary software and configurations to participate in the network.
- Maintaining the Node: Ensuring the node remains synchronized and operational, adhering to the network’s protocols.
Detailed instructions and resources for setting up and maintaining a permissionless node are available in the official Polygon documentation.
4. Upgrade Mechanism and Timelock
The Etrog upgrade follows a structured governance process to ensure transparency and security:
- Timelock Period: A 10-day timelock was initiated on January 27, 2024, providing the community with an opportunity to review and validate the upgrade proposal.
- Upgrade Execution: Upon completion of the timelock, the upgrade was deployed to the mainnet on February 13, 2024.
This governance model ensures that all stakeholders have the opportunity to participate in the decision-making process and that the network remains secure and stable.
5. Forced Transaction Mechanism Status
As of the Etrog upgrade, the forced transaction mechanism is disabled. This decision was made to mitigate the risk of malicious activities during the upgrade process. The forced transaction mechanism allows for the inclusion of transactions in the blockchain without the standard validation process, which could be exploited if misused. By disabling this feature, Polygon zkEVM enhances the security and integrity of the network.
Security and Upgrade Mechanisms
The Etrog upgrade introduces several security enhancements and a structured upgrade mechanism to ensure the integrity and stability of the Polygon zkEVM network. Here’s a detailed breakdown:
1. Timelock Transparency
A 10-day timelock was initiated on January 27, 2024, for the Etrog upgrade, concluding on February 6, 2024. This period allowed the community and validators to review the proposed changes and ensure that the upgrade met security and performance standards. The upgrade was officially deployed on the mainnet on February 13, 2024.
2. Upgrade Proposal and Signature Process
The upgrade process involved submitting a proposal that required signatures from validators. This decentralized approach ensured that the decision to upgrade was community-driven and that multiple stakeholders had a say in the network’s evolution.
3. Forced Transaction Mechanism Status
As of the Etrog upgrade, the forced transaction mechanism is disabled. This decision was made to mitigate the risk of malicious activities during the upgrade process. The forced transaction mechanism allows for the inclusion of transactions in the blockchain without the standard validation process, which could be exploited if misused. By disabling this feature, Polygon zkEVM enhances the security and integrity of the network.
4. Upgrade Governance and Security Council
The upgrade process is governed by a transparent and community-involved mechanism. In cases where immediate upgrades are necessary, the Polygon Security Council can initiate upgrades without the standard delay. However, such actions are subject to scrutiny and are designed to address critical issues promptly while maintaining network security.
Future Roadmap and Ecosystem Developments
The Etrog upgrade marks a significant milestone in the evolution of Polygon zkEVM, but it is not the end of the journey. Several initiatives are underway to further enhance the platform’s capabilities and expand its ecosystem. Here’s an overview of the upcoming developments:
1. Integration with Polygon Chain Development Kit (CDK)
The Etrog upgrade lays the groundwork for the integration of the Polygon Chain Development Kit (CDK), a suite of open-source tools designed to simplify the creation of custom blockchain networks. By adopting CDK, developers can leverage pre-built components to build tailored Layer 2 solutions that meet specific application requirements. This integration aims to foster innovation and accelerate the development of diverse blockchain applications within the Polygon ecosystem.
2. Introduction of AggLayer
AggLayer, short for Aggregation Layer, is a proposed feature that seeks to unify liquidity and state across multiple Layer 2 networks. By aggregating various chains into a single cohesive layer, AggLayer aims to enhance interoperability and scalability, providing a seamless experience for users and developers alike. This initiative aligns with Polygon’s vision of creating a multi-chain ecosystem that operates efficiently and cohesively.
3. Transition to Type 2 ZK-EVM
While the Etrog upgrade brings Polygon zkEVM closer to achieving Type 2 ZK-EVM status, certain features, such as EIP-1559, are not yet supported. Future upgrades are planned to address these gaps, ensuring full compatibility with Ethereum’s EVM. Achieving Type 2 ZK-EVM status will further streamline the deployment of Ethereum-compatible applications on Polygon zkEVM, making it an even more attractive platform for developers.
4. Enhanced Developer Tools and Resources
To support the growing community of developers, Polygon is committed to expanding its suite of developer tools and resources. This includes comprehensive documentation, tutorials, and community support channels to assist developers in building, testing, and deploying applications on Polygon zkEVM. By providing robust tools and resources, Polygon aims to empower developers and foster innovation within its ecosystem.
5. Community Engagement and Ecosystem Growth
Polygon recognizes the importance of community involvement in driving the growth and success of its ecosystem. The platform continues to engage with developers, users, and stakeholders through various channels, including forums, social media, and events. By fostering an inclusive and collaborative environment, Polygon aims to cultivate a vibrant community that contributes to the ongoing development and adoption of its technologies.
Final Note
The Etrog upgrade marks a pivotal advancement in the evolution of Polygon zkEVM, enhancing its scalability, compatibility, and developer experience. By introducing support for additional precompiled contracts, optimizing block production, and restructuring the contract architecture, Etrog brings Polygon zkEVM closer to achieving Type 2 ZK-EVM status. These enhancements empower developers to deploy Ethereum-compatible decentralized applications seamlessly, fostering innovation and adoption within the ecosystem.
Looking ahead, the integration with the Polygon Chain Development Kit (CDK), the introduction of AggLayer, and the pursuit of full Type 2 ZK-EVM compatibility signify Polygon’s commitment to advancing blockchain scalability and interoperability. As the ecosystem continues to grow, the Etrog upgrade serves as a foundational step towards realizing a more efficient and developer-friendly blockchain environment.
For developers and stakeholders, staying informed about these developments and actively participating in the ecosystem will be crucial in leveraging the full potential of Polygon zkEVM and contributing to the broader adoption of decentralized technologies.
