We present biba, a package designed to deal with representations of large automata. It offers a library able to build, even on a modest computer, automata where the sum of the numbers of states and edges achieves one billion or more. Two applications that use this library are provided as examples. They build the reduced automaton for a given vocabulary, and the suffix automaton of a given word. New programs can be developed using this library. In order to overcome physical memory limitations, biba implements a paging scheme, in such a way that the automata really reside on disk, making possible their permanent storage. Through a simple interface suited for perl, small scripts can be easily written to use and extract informations from these automata.