ZK Batch Proofs — Computational Integrity

The L2 (Citrea) periodically writes ZK batch proofs to Bitcoin — mathematical guarantees that every state transition was computed correctly.

How It Works

  1. Every BINST transaction lives in a Citrea L2 block
  2. The sequencer inscribes Sequencer Commitments (Merkle roots) on Bitcoin — pins ordering
  3. The batch prover inscribes ZK proofs (Groth16 via RISC Zero) on Bitcoin with state diffs — proves correctness
  4. Anyone with a Bitcoin node can reconstruct the entire L2 state including all BINST data

Finality Levels

LevelWhat happensHow to verify
Soft ConfirmationSequencer signs the L2 blockTransaction receipt
CommittedSequencer commitment inscribed on Bitcoincitrea_getLastCommittedL2Height
ZK-ProvenZK batch proof inscribed on Bitcoincitrea_getLastProvenL2Height

Why This Matters for BINST

Process instance state reaches Bitcoin via batch proof. This means:

  • A second L2 can verify process execution by reading Bitcoin DA — no messaging protocol needed
  • The taproot-reader can reconstruct which steps were executed, by whom, at what timestamp
  • Cross-chain execution verification is trustless — it goes through Bitcoin, not through any relay

See: Citrea DA Format · Decoding Procedure