The FastUtf8 package provides efficient UTF-8 handling for modern C++ with support for legacy C. It includes a FastUtf8::Uniseries C++ class that allows you to efficiently handle UTF-8 content, integratedly relying on the standard C library for optimized handling of ASCII text. In addition to covering the fundamentals of working with internationalized content, the class includes methods for searching semistructured content more efficiently than prior ASCII-centric techniques could search through ASCII text, and with simpler coding too.