Azul

Overview of the Azul hardfork, introducing Osaka EVM support, a simplified execution client, and a multi-proof system for L2 checkpoints.

Summary

Only base-consensus and base-reth-node will support the Base Azul hardfork. If you are running op-node, op-geth or any other clients you will need to update prior to the activation date.

• Add Osaka Support
• Simplify Flashblocks Websocket Format
• Enable a new multi-proof system for faster withdrawals and a path to stronger decentralization
• Only Base Node Reth / Base Consensus will be supported

Activation Timestamps

Network	Activation timestamp
mainnet	1779386400 (~2026-05-21 18:00:00 UTC)
sepolia	1776708000 (2026-04-20 18:00:00 UTC)

The mainnet activation date is tentative and subject to change. Follow @buildonbase for the latest updates.

Execution Layer

• EIP-7823: Upper-Bound MODEXP
• EIP-7825: Transaction Gas Limit Cap
• EIP-7883: MODEXP Gas Cost Increase
• EIP-7939: CLZ Opcode
• EIP-7951: secp256r1 Precompile
• EIP-7642: eth/69
• EIP-7910: eth_config RPC Method
• Remove Account Balances & Receipts

Proofs

• Proof System
• New/Changed Onchain Components
• Proposer
• Challenger
• TEE Provers
• ZK Provers
• Prover Registrar