AliView is intended to be a simple easy-to-use alignment editor, and not a complete program for phylogenetic analyses. Instead, the ‘external interface’ function is aimed to ease the use of AliView as one program in a chain of software, making it possible to call other programs from within AliView with the current alignment or selected sequences as arguments. As a proof of concept, AliView comes with a preset code that adds a button for directing the alignment to FastTree (Price et al., 2010) that calculates a phylogenetic tree that is then automatically opened in FigTree (Rambaut, 2012).