MD-TUI is a Rust-based terminal markdown viewer (TUI) that renders `.md` files with full keyboard navigation, syntax highlighting via tree-sitter, inline images, foldable `<details>` blocks, mermaid diagrams, table rendering, search, and link following (internal/external/wiki). It can be used as a standalone binary (`mdt`) or as a library. The architecture is monolithic but modular: a custom PEG parser (`src/md.pest`) converts markdown into a component tree (`ComponentRoot`) composed of `TextComponent` and `ImageComponent` nodes; these are rendered to the terminal using `ratatui`. Configuration is loaded from `~/.config/mdt/config.toml` or environment variables. The repository demonstrates strong Rust craftsmanship with well-separated modules, optional feature flags (`tree-sitter`, `network`), thread-local caching for syntax highlighting, and a comprehensive test suite covering parsing edge cases, search, and rendering behavior.