This paper presents and discusses the first Universal Dependencies treebank\nfor the Apurin\\~a language. The treebank contains 76 fully annotated sentences,\napplies 14 parts-of-speech, as well as seven augmented or new features - some\nof which are unique to Apurin\\~a. The construction of the treebank has also\nserved as an opportunity to develop finite-state description of the language\nand facilitate the transfer of open-source infrastructure possibilities to an\nendangered language of the Amazon. The source materials used in the initial\ntreebank represent fieldwork practices where not all tokens of all sentences\nare equally annotated. For this reason, establishing regular annotation\npractices for the entire Apurin\\~a treebank is an ongoing project.\n