Library
Under Code, Library covers reusable packages you import into an application—logging, parsing, clients, utilities—not a full runtime stack. A library gives you an API; it does not own your process lifecycle, routing, or project layout the way a Framework does.
Sibling subcategories: Language (syntax and specs like YAML) and Framework (opinionated app skeletons). Tag an item here when the primary artifact is a dependency you link or install, often per-language (e.g. Zap for GoLang, tree-sitter for parsers).