The lean-stack rule and the evidence rule

Two rules decide what enters the stack (decided).

The lean-stack rule. A new tool joins only to fill a genuine gap the stack can't cover to the required standard, and only when several respected creators show real production results with it and share how they worked. Marketing is never enough. Where no proven tool exists for a job, the best available tool may serve it, labelled [best available, not yet validated], until a proven one clears this rule. A stack tool keeps its place until a challenger clears this rule. New versions are checked each month; evidence from an older version counts at half weight.

The evidence rule. A tool or a default needs several independent sources. A creator family counts once; course sellers, affiliates and vendor case studies don't count. A single strong source enters only as a labelled option. Prices are never evidence. The labels are in Start here → Who it is for, and how to read it.