@zanii/train

Training-data provenance & subject-absence proofs. The claim buyers actually want is negative: "my data was never used to train your model." You can't prove that about the whole world — but you can prove it about a declared run: commit the training set to a sorted-Merkle manifest, then hand a data subject a non-membership proof their ref is absent from it, checkable offline with no trust in the operator.

npm install @zanii/train @zanii/core

import { buildManifest, manifestReceipt, proveAbsence, verifyAbsence } from '@zanii/train';

// the model operator commits the training set (refs are hashes/HMACs, never content):
const manifest = buildManifest({ runId: 'gpt-run-7', refs: memberRefs, createdAt: now });
await zanii.record(manifestReceipt(manifest));   // anchor it into the ledger

// a data subject asks "was my document in it?" — the operator answers with a proof:
const proof = proveAbsence(manifest, memberRefs, userRef);   // throws if actually present
verifyAbsence(proof, manifest);   // TRUE, verified by the subject, offline

Python: from zanii.train import build_manifest, prove_absence, verify_absence, ... — byte-identical manifest roots (locked by a cross-language vector).

How the absence proof works

Sorted-set non-membership — the pattern the Zanii L1's SMT uses. Sort the member refs and Merkle-commit the adjacency leaves (each member, and the gap to the next). To prove x is absent, reveal the one gap (lo, hi) with lo < x < hi plus its inclusion proof in the manifest: since the set is sorted and every gap is committed, a covering gap that verifies means nothing sits between lo and hi — so x is not a member. Membership (proveMembership) is the same machinery on a member leaf. Proofs use @zanii/core's own inclusionProof/verifyInclusion, so they verify with the exact primitive the ledger uses.

The limit, stated up front

This proves what was recorded in the manifest, not what a GPU secretly saw. An absence proof is only as honest as the manifest is complete — pair it with an attested enclave (@zanii/attest: the published image hash is the only code that touched the data) so "absent from the manifest" also means "absent from the run." The manifest commits refs, never content.