This is a monorepo providing a feature-rich sketch-ruler component library for Vue 3, targeting design tools, low-code platforms, and big-screen visualization. It includes a framework-agnostic core package (`@sketch-ruler/core`) with 2D transform engine, plugin system, snap engine, canvas manager, and minimap engine—all zero DOM dependencies. Separate packages handle canvas rendering (`@sketch-ruler/canvas`) with optimized label caching, offscreen caching, and input management (mouse, keyboard, wheel), and a selection engine (`@sketch-ruler/selecto`). The main Vue package (`vue3-sketch-ruler` / `@sketch-ruler/sketch-ruler`) provides Vue components (SketchRuler, Minimap, RulerLine) plus composables for canvas transform, ruler scale, and snap detection. The architecture is cleanly layered, well-tested with Vitest, and shipped via npm. The demo site showcases multiple use cases (editors, whiteboards, org charts, big-screen displays). The code demonstrates mature engineering with reusable patterns, though the large monorepo and external demo dependencies introduce some maintenance surface.