📊 OnlyCSharp.Sheets - a real formula engine, wired

Every Total below is computed at build time - A1-style cell references, arithmetic, and dependency recalculation - not a typed-in number. Green cells are formulas (their source is shown beneath the value). Re-authored as .razor; the totals are evaluated live in C#.

formula-engine self-test: 12 KATs passed ✓

	A	B	C	D
1	Item	Qty	Price	Total
2	Apples	3	2	6=B2*C2
3	Bread	5	4	20=B3*C3
4	Coffee	2	10	20=B4*C4
5	Total			46=D2+D3+D4

↻ live dependency recalculation

Edit B2 (Apples qty): 3 → 10
the engine recomputes every dependent automatically:
D2 =B2*C2: 6 → 20
D5 =D2+D3+D4: 46 → 60

Built BCL-only, AOT-clean. The spreadsheet brain (ComputerScience.Fast.Sheet.OcSheet) already ships in the library; this page is the proof the engine is real, now authored as .razor -> static HTML.