Impeccable is a design-quality and anti-pattern detection engine for front-end web projects, primarily targeting AI-generated UI. It provides a Rust-based CLI, a WASM browser extension core, and a distributed skill system that plugs into over 20 AI coding assistants (Claude, Cursor, Gemini, etc.). The system runs deterministic detection rules against HTML/CSS to flag common issues like poor contrast, typography problems, layout flaws, and 'AI slop' patterns, and also supports live browser iteration with session management, component review workflows, and comp-vs-build image comparison. All detection logic is implemented as a port of a JavaScript reference, with extensive vector-replay tests to maintain byte-for-byte behavioral parity. Architecturally, the repository is a large Rust workspace with 14+ crates handling distinct concerns: static HTML parsing and CSS cascade (`crates/html`), rule evaluation (`crates/foundation`, `crates/core`), browser automation via CDP (`crates/browser`), live-mode HTTP servers and session management (`crates/live`), and skill packaging/distribution (`crates/skills`, `scripts/`). A Chrome DevTools extension embeds the WASM core for in-page scanning. The project is actively maintained with respect to both the Rust core and the constantly shifting AI-harness integration surface, though that breadth introduces significant drift risk across duplicated skill assets and provider-specific configuration. The codebase demonstrates strong engineering discipline—clean abstractions, pervasive testing, and careful parity management—but the sheer scale and duplication in the skill/plugin tree reduces overall reusability.