--- a/src/osforge/merge.py
+++ b/src/osforge/merge.py
@@ -937,0 +938,11 @@
+def replace_package(src_root: Path, build_dir: Path, pkg: str) -> bool:
+    """Replace an authoritative package without redundant comparisons."""
+    src = src_root / pkg
+    if not src.is_dir():
+        return False
+    dest = build_dir / pkg
+    remove_path(dest)
+    copy_tree_merge(src, dest)
+    return True
+
+
@@ -1099,1 +1110,1 @@
-        if copy_package(seed_sources[rel], build_dir, rel):
+        if replace_package(seed_sources[rel], build_dir, rel):