ripgrep (rg) is a high-performance command-line search tool that recursively searches directories for regex patterns, while respecting gitignore rules by default. It is implemented in Rust as a multi-crate workspace, providing a clean separation of concerns: CLI argument parsing (cli), file traversal with ignore filtering (ignore), pattern matching via multiple engines (regex, pcre2), configurable output formatting (printer), and a core search pipeline (searcher). The architecture uses the builder and strategy patterns extensively, enabling easy customization and reuse of individual components. Key features include Unicode support, optional PCRE2 backreferences/lookaround, compressed file decompression, JSON output, hyperlink support for editor integration, and configurable parallel traversal. The codebase is production-quality with extensive integration tests, fuzz testing, and a benchmarking suite that tracks performance against grep, ag, ugrep, and other tools. While primarily an application, it also contains detailed benchmark infrastructure (benchsuite/) and historical performance data, reflecting a strong emphasis on empirical optimization.