diagram, dplyr, stringr, tidyr, magrittr, methods, purrr,
rlang, tibble, Rcpp (>= 0.11.5)
knitr, Matrix, rmarkdown, testthat, readr, xml2, covr
knitr, Matrix, rmarkdown, testthat (>= 3.0.0), readr, xml2,
covr, roxygen2