\doabstract{Consolidation of expl3} {Morten H\o gholm} {The expl3 language used as the foundation of \LaTeX3 has gone through a consolidation phase where almost each and every concept has been questioned, taken apart and put back. Sometimes in the same form as it was and sometimes in radically different forms. We will go through some of the most interesting changes and highlight the areas where special effort has been made to ensure simple and natural interfaces.}