Abstract
Spot is a library of model-checking algorithms started in 2003. This paper focuses on its module for translating linear-time temporal logic (LTL) formulas into Büchi automata: one of the steps required in the automata-theoretic approach to LTL model-checking. We detail the different algorithms involved in this translation: the core translation itself, which performs many simplifications thanks to its use of binary decision diagrams; the pre-processing of the LTL formulas with rewriting rules chosen to help their translation; and various post-processing algorithms whose use depends on the intent of the translation: do we favor deterministic automata, or small automata? Using different benchmarks, we show how Spot competes with other LTL translators, and how it has improved over the years.