SheetProof

SheetProof is a local-first trust layer for business-critical Excel workbooks.

It focuses on deterministic spreadsheet auditing:

• workbook parsing
• formula inventory
• dependency graphing
• formula consistency checks
• hardcoded override detection
• hidden/external dependency detection
• workbook diffing
• assumption extraction
• assumption delta tracking between workbook versions
• risk scoring
• evidence-backed report generation

Status

Implemented:

• deterministic audit pipeline
• workbook diff pipeline
• local explain (Ollama) with deterministic-artifact guardrails

Quick Start

python -m venv .venv
source .venv/bin/activate
pip install -e .[dev]
sheetproof --help
pytest

Commands

sheetproof audit workbook.xlsx
sheetproof audit workbook.xlsx --policy-pack finance
sheetproof diff old.xlsx new.xlsx
sheetproof diff old.xlsx new.xlsx --policy-pack compliance
sheetproof gate --workbook workbook.xlsx --max-high-risk-findings 5 --max-external-references 0
sheetproof gate --old-workbook old.xlsx --new-workbook new.xlsx --max-new-hidden-sheets 0
sheetproof explain workbook.xlsx --cell "Summary!F12"

explain requirements:

• run audit first for the same workbook (uses .sheetproof deterministic artifacts)
• enable local LLM in config (sheetproof.yml):

llm:
  enabled: true
  provider: "local"
  model: "qwen"
  base_url: "http://localhost:11434"

Output Artifacts (target MVP)

• .sheetproof/workbook-index.json
• sheetproof-report.md
• sheetproof-report.json
• risk-cells.csv
• formula-map.json
• dependency-graph.json
• assumption-register.csv
• workbook-diff.json
• assumption-diff.json
• reproducibility-manifest.json

Policy Packs

Deterministic policy packs are supported:

• finance
• compliance
• operations

Use --policy-pack to apply one. Policy packs control deterministic severities, volatile-function handling, and high-risk sheet lists.