SheetShift · rating spreadsheets to verified code

Loading run status...

Your rating spreadsheet, as code you own, checked cell by cell

SheetShift uses IBM Bob to translate the workbook that prices your policies into a tested Python service. A grader that Bob cannot edit compares every output cell with the original workbook, and a person decides every place where the workbook disagrees with the filed rating manual.

Reconciliation

Loading the certificate…

Full certificate · certificate.json

Measured next to the headline

Harness sensitivity

What a spot check misses

Traceability

Time

See it in three clicks

  1. Verify: run Bob's service live on up to 500 recorded policies and compare every output with the recorded workbook values.
  2. Trace: pick a workbook column and see the function that computes it, with its tests; or pick a function and see its cells.
  3. Certificate: the hashes, the signed decisions, the mutation self-test and the limits.

How it works

Map

A deterministic tool dumps the workbook's formulas into column rules, splits them into four units and lints the anomalies.

Translate

IBM Bob plans from the workbook and the manual, then translates each unit in parallel, tagging every function with the cells it covers.

Verify

The service and a recorded LibreOffice recalculation of the workbook are compared on 10,000 policies, including boundary cases.

Triage

Mismatches are grouped by root cell. Translation bugs go back to Bob; spreadsheet anomalies go to a person.

Decide

A teammate acting as pricing lead decides each anomaly, citing the filed manual rule. The decision is logged, never made by Bob.

Certify

The certificate hashes the workbook, code, grader and inputs, and lists everything that is not verified.

Limits

  • Evidence over sampled and boundary inputs, not a formal proof.
  • The oracle is LibreOffice 24.2 with full recalculation forced, not Excel; Excel parity is unverified unless the optional cross-check runs.
  • Macros and VBA are not supported; .xlsm files are never opened.
  • Volatile functions (NOW, TODAY, RAND, OFFSET, INDIRECT) are reported as unsupported.
  • External links, array and dynamic-array formulas, data tables and iterative calculation are out of scope.
  • The three anomalies in the demo workbook were seeded by the team, and all data is synthetic.