Validity Rollup

Overview

A validity rollup batches off-chain execution and proves the resulting state transition to a settlement-layer contract. The contract accepts a new state commitment only when the submitted validity proof verifies against the required public inputs. Proofs can use SNARK, STARK, or related systems. Unlike an optimistic rollup, correctness does not depend on waiting for a fraud-challenge period, although proof generation, data publication, and settlement still take time.

Validity proves correct execution under the encoded circuit, but users also need available data to reconstruct state and transact independently. Evaluators should examine the proof system, trusted setup, sequencer, prover concentration, bridge contracts, upgrades, and data-availability mode. Validity security does not automatically provide privacy, censorship resistance, or immediate Ethereum finality. A transaction accepted by a sequencer has not necessarily been published, proven, finalized on the base layer, or made withdrawable. Validity Rollup should be described through its execution, sequencing, data-publication, proof or challenge, bridge, and settlement stages.

The security model for Validity Rollup includes sequencer control, proof or fault-resolution rules, data availability, bridge contracts, upgrade keys, and the base-layer verifier. A cryptographic proof can reduce execution trust while leaving censorship, data, governance, and contract risks.

Fulfillment and withdrawal policies should use the stage that matches the business risk. Payment applications using Validity Rollup should maintain separate states for local acceptance, batch publication, proof verification or challenge completion, bridge execution, and base-layer finality. Production support needs monitoring for sequencer outages, delayed batches, proof failures, forced-inclusion paths, contract pauses, and upgrade events. Users should have a documented route to recover or exit when the preferred sequencer, prover, or interface is unavailable.