H33-74 on Optimism

Optimism is one of H33-74's anchor surfaces, not its foundation. The receipt exists before the Optimism anchor and remains valid if the Optimism anchor is later supplemented or replaced on another chain. Optimism provides one independent notarization. H33-74 receipts can carry many.

How H33-74 anchors to Optimism

H33-74 anchors to Optimism via EIP-1559 calldata commitments. As the founding OP Stack chain, Optimism settlement assurance inherits from Ethereum L1.

Chain parameters

Chain

Optimism (chain ID 10)

Finality

L2 soft finality in seconds; L1-inherited hard finality on Ethereum settlement (~7 days for full challenge window, ~hours typical).

Anchor cost

Low cost (typically 10x to 100x cheaper than Ethereum L1).

Explorer

optimistic.etherscan.io

What an H33-74 anchor record contains

The 32-byte commitment from the receipt (or a Merkle root if batched).
Sufficient on-chain bytes for a third party to verify the commitment matches the receipt.
A timestamp from the Optimism block, providing independent proof that the receipt existed by no later than that block.

What it does not contain: sensitive payload data. The receipt's content lives off-chain. The anchor only commits to its existence and identity.

When Optimism is the right anchor

Optimism is the right anchor when EVM compatibility is required, when established L2 tooling and governance (Optimism Collective) are valuable, and when L1-grade settlement assurance through optimistic rollup is sufficient. Particularly appropriate for governance-heavy use cases that benefit from Optimism's RetroPGF and citizen governance model.

The portability story

A receipt anchored on Optimism can also be anchored on Bitcoin, Ethereum, Solana, Polygon zkEVM, Zcash, or any other chain H33-74 supports. The anchors are independent. Adding more anchors does not change the receipt. Removing one anchor (or having one chain become unavailable) does not invalidate the others.

If Optimism ever becomes inappropriate for an operator's use case (regulatory, performance, security, cost), the operator adds an anchor on a different chain and continues operating. The historical evidence does not have to migrate, because it was never bound to Optimism.

Verifying a Optimism anchor

A third-party verifier needs the H33-74 receipt, the Optimism anchor transaction (or its hash), and the open-source H33 verifier. From those inputs:

The verifier checks the three post-quantum signatures over the receipt.
The verifier checks that the Optimism anchor transaction commits to the receipt's identity.
The verifier reads the Optimism block timestamp to establish independent existence-time.

See H33-74 on other chains

The same receipts that anchor to Optimism can anchor to any of the others.

One Receipt. Multiple Chains. H33-74 Overview