GOPLang: Universal Language as Parameter Space is an interdisciplinary academic book about a deceptively simple question: how much of a linguistic structure may disappear from the surface while its intended organization remains recoverable? The book reframes the long-standing dream of a universal language. Instead of proposing one culturally neutral code or a replacement for natural languages, it proposes a constrained family of linguistic realizations generated from a shared architecture. Different profiles can distribute evidence through morphology, word order, context, prosody, discourse, convention, memory, and repair, while remaining traceably related to one another.