Caps MODEXP precompile inputs to a maximum of 1024 bytes per field. Calls with larger inputs are rejected.

Introduces a protocol-level maximum gas limit of 16,777,216 (2^24) per transaction. Transactions above this cap are rejected during validation, and Base adopts the same cap as L1 to maximize Ethereum equivalence. Deposit transactions will be exempt from the transaction gas limit cap. They are already limited to 20,000,000 gas as that is the most gas that can be included in an L1 block.

Raises the MODEXP precompile minimum gas cost from 200 to 500 and triples the general cost calculation.

Adds a new CLZ opcode that counts the number of leading zero bits in a 256-bit word, returning 256 if the input is zero.

Specifies the secp256r1 precompile at address 0x100. From Azul, the gas cost increases to 6,900 to match the L1 gas cost specified in EIP-7951.

Updates the Ethereum wire protocol to version 69, removing legacy fields from the Status message and simplifying the handshake.

Simplifies the FlashblocksMetadata payload by removing new_account_balances and receipts from the Flashblocks WebSocket format.

Updates execution-layer discovery to use basev0 as the protocol ID so Base nodes can find each other more quickly, especially on smaller networks like Sepolia.

Introduces the eth_config JSON-RPC method, which returns chain configuration parameters such as fork activation timestamps.

At and after Azul activation, block production and import use the following Engine API methods: engine_forkchoiceUpdatedV3 for starting block builds and forkchoice synchronization. engine_getPayloadV5 for fetching built payloads. engine_newPayloadV4 for importing payloads into the execution engine. engine_getPayloadV5 returns a V5 envelope, but the contained execution payload is still V4-shaped. As a result, payload insertion continues through engine_newPayloadV4 (there is no engine_newPayloadV5 path used by Base Azul clients).Azul constraints for this flow: Blob-related Engine API inputs are constrained to empty values: expectedBlobVersionedHashes MUST be an empty array. blobsBundle in engine_getPayloadV5 responses is expected to be empty. executionRequests in engine_newPayloadV4 MUST be an empty array.

Proof System Introduces a multi-proof system for L2 checkpoints, where AggregateVerifier can verify one or two proofs for the same proposal before withdrawals rely on it. New/Changed Onchain Components Adds AggregateVerifier plus proof-specific verifier contracts, reduces DelayedWETH to a 1-day withdrawal delay, and moves legacy finality timing out of OptimismPortal2 and AnchorStateRegistry. Proposer Turns safe or finalized Base L2 checkpoints into L1 AggregateVerifier games by requesting TEE proofs, verifying output roots, and submitting proposals with the required bond. Challenger Checks in-progress AggregateVerifier games against canonical L2 state and disputes incorrect claims through the permissionless ZK proof challenge path. TEE Provers Adds AWS Nitro Enclave-backed TEE provers for the common proposal path. The enclave re-executes requested L2 block ranges and signs resulting checkpoint outputs. ZK Provers Adds permissionless ZK provers for dispute verification, especially to challenge invalid TEE-backed proposals or invalidate bad ZK claims. Prover Registrar Keeps the onchain TEEProverRegistry in sync with the live set of Nitro prover signers, attesting active signer identities and removing orphaned signers.