Summary of Changes

This section summarizes the changes from the generalized optimistic rollup architecture that are required to integrate an optimistic rollup with the Espresso Sequencer. Though the changes are presented in terms of an abstracted architecture, if you can map this abstraction onto your specific optimistic rollup, you can derive a very concrete to-do list for integrating your rollup with the Espresso Sequencer.
  1. 1.
    Modify JSON-RPC or analogous server to forward transactions from users to the Espresso Sequencer. Choose a numeric ID for your rollup and attach it to the forwarded transactions.
  2. 2.
    Modify proposers and challengers to stream notifications of new blocks from either:
  3. 3.
    Modify proposers and challengers to download full blocks, or rollup-specific subsets of blocks, from the sequencer availability API.
  4. 4.
    Extend proposers and challengers to include, in the event of a challenge
  5. 5.
    Modify the rollup contract to read block commitments from the sequencer contract instead of its own storage.
  6. 6.
    Extend the rollup contract to verify the completness/inclusion proof and Merkle proof provided by proposer and challenger.
  7. 7.
    (Optional) Extend the challenge protocol to encode a deterministic reordering of the transactions provided by the Espresso Sequencer.