Proof & Trust · Ribbon group: Proof
Bind, sign, and prove every number.
The cryptographic moat. Bind inputs to their source with SHA-256, anchor reviewer attestations in an append-only hash-chain ledger, replay material change drivers live through Excel, and export tamper-evident certificates. Proof of derivation travels with the workbook.
Proof & Trust
Bind, sign, and prove every number.
Demo comingFlagship features
The 5 that matter most.
The features inside this capability that drive the most buyer interest.
Why This Number
Click any cell, see the full causal chain — sources, formulas, signatures, and timestamps.
Bind Source
Pin an input to a URL, file, prior workbook, or note — SHA-256 snapshot detects drift.
Sign Formula Block
Attest a contiguous range sharing the same R1C1 formula — the analyst signs once for the whole block. Each block carries a signature hash over scope + master R1C1 + variants; R1C1 divergence on any cell in the block surfaces as drift on next verify.
Proof Coverage
Workbook-wide score: percent inputs bound, percent formulas signed.
Export Proof Certificate
Snapshot the workbook's current Proof state into a portable certificate (JSON, PDF, or branded export) anchored to the ledger head hash. Any tool that can compute SHA-256 can recompute the certificate hash and confirm tamper-evidence — Node's built-in crypto, OpenSSL, Python hashlib. (Distinct from Replay Proof, which signs an output-delta replay rather than a workbook snapshot.)
Also in this capability
5 more features.
- Bind VectorBind a contiguous input range as one atomic unit; one edit invalidates the whole vector.
- Sign CellAppend a reviewer attestation to one cell with claim text and notes. The attestation is anchored to the workbook's append-only hash-chain ledger — any subsequent edit to the formula's canonical R1C1 form breaks the chain on next verify.
- Replay ProofPick any output cell that has changed. Replay Proof saves a copy of the baseline workbook to temp, opens it in live Excel, applies each revised driver, and recalculates the output after each step — actual formulas, UDFs, and named ranges executing in Excel, not a simulator. Up to 8 ranked drivers; per-driver dependency path from input to output; per-driver trust status (vector fresh/broken, block signed/broken, bound, no record). Two layers of integrity: every export is a tamper-evident SHA-256 self-hash certificate, and `.mxreplay` exports also write a sibling `.mxreplay.signed` envelope — a real Ed25519 asymmetric signature (BouncyCastle Ed25519Signer) over the canonical certificate plus envelope metadata, with the public key embedded in the envelope. Per-user keypair generated on first launch, private key sealed with DPAPI at `%APPDATA%\ModelxcelPro\keys\`. The repo ships a zero-dependency Node verifier (`tools/verify-replay/verify-replay.js`) that any auditor can run against `.mxreplay.signed` without installing ModelxcelPro. Issuance writes a CertificateIssued record back into the workbook ledger so the audit trail captures every export.
- Verify All Vectors & BlocksBulk recompute every bound vector and signed block; flag drift in one pass.
- Verify LedgerRecompute the workbook's hash chain; detect tampering or reordering of the proof history.
Same product, more capabilities