Search Walks To User Writable

A hierarchical name-resolution algorithm (executable PATH, dynamic-linker library search, language-runtime module resolver) walks up a directory tree generating candidate paths at each level and terminates at a system-defined root. The algorithm was authored against a platform whose terminal node is administrator-owned and treats that ownership as the implicit allowlist on the lookup-path list. The deployment platform places the terminal node inside a user-writable trust zone. First-match-wins resolution accepts the standard user's planted artifact over the legitimate one further down the walk.