Part of a larger dissertation research, the paper will investigate preliminary data on the codeswitching and language mixing use of Javanese (a local language), Bahasa Indonesia or BI (the national language) and English by youth, both in conversations as well as in writing, in the city of Semarang in Central Java, Indonesia, a multilingual developing country of the global South. The preliminary findings indicate that youth in Semarang use Javanese, BI and English under a norm of polylingualism, with Javanese and BI being the predominant bilingual medium in spoken conversation. Gaul Indonesian, a sub-dialect of BI, acts as an intermediate scale between local and global scales of language. While BI is predominantly used in writing, the use of Javanese re-emerges in the least regulated and most informal domains of writing. The youth in this study use English more in writing than in spoken conversation, using it as a means of expressing a voice that is locally different and resonates with global popular culture but for the purpose of expressing very local and personal expressions.