Forward Compatibility / Strong Validation
Kind: tension
Record: tension:forward-compatibility-strong-validation
Canonical: Schema
"forward-compatibility" (contracts-core layer) is traded against "Strong Validation" (contracts-core layer) — a principle cannot be scope-separated from a quality, metric, or cost it competes with; resolve by measuring "Strong Validation" and choosing an explicit operating point.
Listed in Tensions, after Backward Compatibility / Cleanup / Simplification and before Versioning / Version Sprawl.