Formosa is a Ruby library for processing Taiwanese languages. Major languages spoken in Taiwan include Holo, Hakka, Mandarin and those of the indigenous people. Formosa is the Ruby branch of the lib-formosa project (http://code.google.com/p/lib-formosa/). Currently, we focus on the processing of the Holo (Southern Min) language, with necessary tools such as SyllableComposer available for general use. WWW: http://formosa.rubyforge.org/