R/qtl2 provides a set of tools to perform quantitative trait locus (QTL) analysis in experimental crosses. It is a reimplementation of the R/qtl package to better handle high-dimensional data and complex cross designs. This package is designed to make it easy to install and load multiple R/qtl2 packages in a single step. Broman et al. (2018) <doi:10.1534/genetics.118.301595>.