Ruby gem (native extension in Rust) providing implementations of various string metrics. Current metrics supported are: Sørensen–Dice, Levenshtein, Damerau–Levenshtein, Jaro & Jaro–Winkler. Strings that are UTF-8 encodable (convertible to UTF-8 representation) are supported. All comparison of strings is done at the grapheme cluster level as described by Unicode Standard Annex #29 (https://www.unicode.org/reports/tr29/#Grapheme_Cluster_Boundaries); this may be different from many gems that calculate string metrics.