Base, the Ethereum layer-2 network developed by Coinbase, activated the Azul upgrade on its mainnet on May 29, 2026. This marks the first independent protocol upgrade for Base after departing from the Optimism Superchain, underscoring its push toward technical autonomy and enhanced decentralization.
The core of Azul is a multiproof architecture that combines trusted execution environment (TEE) proofs with zero-knowledge (ZK) proofs. Either proof type can finalize a proposal independently, but when both reach the same conclusion, withdrawal finality can be reduced to just one day. Permissionless ZK proofs are designed to override permissioned TEE proofs in the event of a conflict — a safeguard the Base team describes as critical for censorship resistance and full decentralization.
Alongside the proof upgrade, Base unified its infrastructure under a new client stack: base-reth-node as the execution client and base-consensus (built on OP Kona) as the consensus client. The switch has already produced measurable gains: empty blocks plummeted from roughly 200 per day to about two, and the network sustained multiple bursts of 5,000 transactions per second. Azul also incorporates the CLZ opcode and aligns with Ethereum’s Osaka execution-layer repricing specifications, meaning most application developers need no significant code changes. Node operators still relying on op-node, op-geth, nethermind, or kona must migrate to the new software.
Base rigorously tested Azul on its testnet in April and held an Immunefi audit competition with a $250,000 reward pool for critical bugs. The upgrade arrives with Base commanding approximately $4.4 billion in total value locked and nearly $4.98 billion in stablecoin market cap — leading USDC liquidity among optimistic rollups. Looking ahead, Base has two more upgrades planned for the second half of 2026: a performance-focused release by the end of June and a user-experience update around late August, paving the way for native account abstraction as part of its Stage 2 decentralization roadmap.
