Celo L2 Specification

Table of Contents

This document describes the differences between the Celo L2 implementation and Optimism's OP Stack, on which it is based. Refer to the OP Stack specs for details on the unmodified OP Stack.

The L1→L2 migration changes page details the differences compared to the Celo L1 blockchain. The Celo L2 is a continuation of the L1 by using its state and providing a high level of compatibility with it.

Background

Since May 2024, the Celo Community has decided to transition from an L1 blockchain to a L2 solution using the OP Stack. This move, detailed and approved in CGP-133, aims to enhance scalability, security, and interoperability with Ethereum. The proposal aligns with Celo's mission to create a more accessible and inclusive financial system. By leveraging the OP Stack, Celo L2 will retain the benefits of the existing ecosystem while integrating with Ethereum's robust infrastructure, fostering greater innovation and user engagement.

New Features

Technical Differences

Deployments

Alfajores

The Alfajores testnet will be migrated to an L2 on September 26, 2024. The migration is scheduled for block 26384000. For this L1 chain will be stopped at a block height of 26383999. At this point the existing state will migrated to work with the L2 nodes. The migration process preserves the full L1 history while updating it to work with the Celo L2 stack. More technical details are available in the migration docs.

The Alfajores L2 testnet will have the following chain properties:

  • Block period: 1 second
  • Block gas limit: 30,000,000 gas
  • Block gas target: 6,000,000 gas (see EIP-1559 elasticity multiplier)
  • EIP-1559 elasticity multiplier: 5
  • EIP-1559 denominator: 400
  • EIP-1559 floor: 25 Gwei