Scope agreed before anything gets built.
The first pass is deliberately narrow, and widened only on request. Each stage writes down what it changed and why. Anything that could not be filled is stated plainly rather than padded.
Legal-entity grouping
Deciding whether branches roll up to one parent or stand alone, and applying it consistently.
Validation
Checking structure and reachability before a file is used, not after.
Exclusion log
A record of what was removed and why, delivered alongside the file it came out of.
The first build is deliberately small, by preference.