EIP-7862: What & why

Header carries the previous block's post-state root. No new fields.

• Problem: state-root computation blocks efficient building/proving
• Fix: defer the root by one block
• One root per slot, not thousands during the auction
• Computation frontloaded, off the attestation path
• Composes with BALs (7928) to parallelize the root

Cost: light clients +1 slot for proofs; reorgs recompute the root

EIP-7862: Spec

class BlockChain:
    last_computed_state_root: Root          # tracked across blocks

def validate_header(chain, header):
    if header.state_root != chain.last_computed_state_root:   # delayed root
        raise InvalidBlock

def state_transition(chain, block):
    validate_header(chain, block.header)
    block_output = apply_body(...)
    chain.last_computed_state_root = state_root(block_env.state)  # for NEXT block

• Fork F: init root to post-state of F-1
• F+1 onward: each block carries its parent's root

EIP-8146: What & why

BAL leaves the ExecutionPayloadEnvelope, ships as an independent sidecar.

• Problem: BAL (~70 KiB, up to 1 MiB) increases envelope size
• Fix: separate gossip topic
• Commitment in signed bid: no separate signature
• PTC vote enforces availability at the deadline
• Early delivery: EL prefetches / starts post-state root
• Useful for FOCIL to build ILs based on the latest state

Overhead: same bytes, one hash_tree_root

EIP-8146: Spec

# ExecutionPayload: BAL removed
# ExecutionPayloadBid:
block_access_list_root: Root
# PayloadAttestationData:
block_access_list_present: boolean

class BlockAccessListSidecar:
    beacon_block_root: Root
    slot: Slot
    block_access_list: BlockAccessList