aztec-ethereum

L1 (Ethereum) client and L1↔L2 messaging helpers.

Source: crates/ethereum/src/.

Module Map

Messaging Types

pub struct L1Actor {
    pub address: EthAddress,
    pub chain_id: u64,
}

pub struct L2Actor {
    pub address: AztecAddress,
    pub version: u64,
}

pub struct L1ToL2Message {
    pub sender: L1Actor,
    pub recipient: L2Actor,
    pub content: Fr,
    pub secret_hash: Fr,
}

generate_claim_secret() -> (Fr, Fr) produces a random (secret, secret_hash) pair suitable for funding claim-based flows (e.g. Fee Juice deposits).

L2Claim / L2AmountClaim / L2AmountClaimWithRecipient carry the L2-side data needed to consume a bridged deposit.

L1 Client

use aztec_ethereum::l1_client::{EthClient, L1ContractAddresses, send_l1_to_l2_message};

let eth = EthClient::new(&EthClient::default_url());
let account = eth.get_account().await?;
let tx_hash = eth.send_transaction(/* ... */).await?;
let receipt = eth.wait_for_receipt(&tx_hash).await?;

EthClient is a minimal JSON-RPC client: rpc_call, get_account, send_transaction, wait_for_receipt. L1ContractAddresses can be produced from the Aztec node’s NodeInfo via L1ContractAddresses::from_json(...).

Sending L1 → L2

let result: L1ToL2MessageSentResult = send_l1_to_l2_message(
    &eth,
    &l1_addresses,
    &message,
).await?;

Returns the L1 tx hash and the on-L2 message hash / leaf index needed later for consumption.

Fee Juice Bridge

let FeeJuiceBridgeResult { claim, .. } = prepare_fee_juice_on_l1(
    &eth,
    &l1_addresses,
    recipient,
    amount,
).await?;
// `claim` can be handed to `FeeJuicePaymentMethodWithClaim` in `aztec-fee`.

Cross-Chain Readiness

use aztec_ethereum::cross_chain::{is_l1_to_l2_message_ready, wait_for_l1_to_l2_message_ready};

if is_l1_to_l2_message_ready(&node, &message_hash).await? {
    // safe to consume on L2
}

// Or block until ready:
wait_for_l1_to_l2_message_ready(&node, &message_hash, timeout).await?;

The readiness check queries the node’s archiver for L1-to-L2 message checkpoints.

Full API

Bundled rustdoc: api/aztec_ethereum/. Local regeneration:

cargo doc -p aztec-ethereum --open

See Also

• aztec-fee — consumes L2AmountClaim for claim-based fee payment.
• Architecture: Ethereum Layer
• Concepts: Cross-Chain Messaging