Dialects (Sheets vs Excel)
Behavior differences between the Google Sheets and Excel engine flavors, and why you must always pick one.
Stub — TrueCalc requires an explicit engine flavor (sheets or excel) on
every public entry point; workbooks are engine-locked at creation. This page
will catalogue the observable differences (date serial epochs, function
behavior, error messages), each backed by a fixture ID from truecalc/core.