cross-functional-spreadsheet-buildlisted

Builds a spreadsheet somebody else will maintain: inputs, calculations and outputs on separate sheets, no constants buried inside formulas, a documented assumptions block, a checks sheet that fails loudly, and a written refresh procedure. Use when producing a model, tracker, budget, forecast, pricing sheet, reconciliation or allocation workbook that will be reopened next month by someone who did not build it. Trigger on 'build me a spreadsheet', 'make this into an Excel model', 'turn this into a workbook', 'build a forecast/budget/pricing model', 'can you produce an xlsx', 'this sheet keeps breaking'. Not for checking numbers already produced by a report or dashboard (use data-analytics-report-qa), not for agreeing what a metric means before it is modelled (use data-analytics-metric-definition), and not for writing the narrative that accompanies a variance (use finance-budget-vs-actual-commentary).
alihusains/enterprise-skills · ★ 0 · Data & Documents · score 73

Install: claude install-skill alihusains/enterprise-skills

# Building a maintainable spreadsheet ## Purpose A workbook produced in one pass and handed over is almost always structurally unmaintainable: a growth rate typed inside a formula, an override pasted over a calculated cell, an assumption that exists only in the author's head. It gives the right answer once and then quietly gives wrong answers for a year. This skill fixes the layout, the formula rules, the assumptions block and the self-checks so that the next person can change an input without reverse-engineering the author. ## Prerequisites Check all three **before** building anything. If any is missing, name it and stop — do not produce a partial workbook or a CSV substitute without saying so. - **Inputs:** the actual data (file, table, or explicit figures), the periods and grain, the outputs the reader needs, and every assumption that is not derivable from the data. If assumptions are missing, list the ones you need and stop; a model built on invented rates is worse than no model. - **Runtime:** code execution, plus a spreadsheet-writing library available in the environment — commonly `openpyxl` or `xlsxwriter` for `.xlsx`. Verify by import at step 0. If neither is importable, say which is missing and stop. Do not build the whole model and discover this at the write step. - **Formula support:** if the workbook must contain **live formulas** rather than pasted values, confirm the library writes formula strings. A library that only writes values cannot p