# Lighthouse EIP-7886 Task Breakdown
The following checklist will be used to track progress of CL related changes for EIP-7886, delayed execution.

## Engine API
- **New Structs**
- [ ] Define `JsonExecutionPayloadEip7886` with all EIP‑7886 fields
- [ ] Implement `From` / `TryFrom` conversions between `JsonExecutionPayloadEip7886` and `ExecutionPayloadEip7886`
- **HTTP constants**
- [ ] Add `ENGINE_NEW_PAYLOAD_EIP7886`
- [ ] Add `ENGINE_GET_PAYLOAD_EIP7886`
- [ ] Update `LIGHTHOUSE_CAPABILITIES`
- **Payload handling**
- [ ] Implement `new_payload_eip7886`
- [ ] Implement `get_payload_eip7886`
- [ ] Integrate new methods into `notify_new_payload` and `get_payload_for_header`

## Block Proposal
- **New Structs and Variants**
- [ ] Add `ExecutionPayloadEip7886` variant with `pre_state_root` and `parent_*` fields
- [ ] Define `ExecutionPayloadHeaderEip7886` with matching fields
- [ ] Add eip7886 variant to`latest_execution_payload_header_mut`
- [ ] Implement `upgrade_to_eip7886` to convert old style header to `ExecutionPayloadHeaderEip7886` past fork boundary
- [ ] Add `BlindedPayloadEip7886` variant and conversions
- [ ] Update payload to header `From` implementations for `ExecutionPayloadEip7886`
- [ ] Add match arm in `ExecutionPayloadBodyV1::to_payload` for `ExecutionPayloadHeader::Eip7886`
- **Payload Reconstruction**
- [ ] Combine `BlindedPayloadEip7886` with body to reconstruct `ExecutionPayloadEip7886`
- **Beacon State & Fork Upgrade**
- [ ] Add `BeaconStateEip7886` with `latest_execution_payload_header`
- [ ] Implement `upgrade_to_eip7886` state migration
- [ ] Register fork upgrade at the configured epoch
- **Block Construction**
- [ ] Update `complete_partial_beacon_block` to handle `ExecutionPayloadEip7886`
- [ ] Ensure `process_execution_payload` fills temp state with the new variant

## Block Validation
- **Validation Path Updates**
- [ ] Update `notify_new_payload` to call `engine_newPayloadEip7886`
- [ ] Store `ExecutionPayloadHeaderEip7886` in canonical state after validation
- **Block Hashing**
- [ ] Extend `ExecutionBlockHeader` with `pre_state_root` and `parent_*` fields
- [ ] Modify `calculate_execution_block_hash` accordingly

## Testing
- TBD