Writing design docs REQUIRED BACKGROUND: the skill (read-first, hard rules, truth rules, style). Overview A design document is a proposal made discussable: conclusion first, every non-trivial choice in a Why & What box, costs named next to benefits, and fact separated from proposal. When to invoke, and not Invoke for anything that argues for a change or records a design: proposals, RFCs, design docs, specs, migration plans, "should we" documents. Do NOT invoke for recording an already-taken decision ( ), for procedures ( ), or for status reports. Under pressure: a proposal persuades with its…