curl, sys, stats, utils, rappdirs, digest
curl, sys (>= 2.1), stats, utils, rappdirs, digest
curl, sys (>= 2.1), stats, utils, digest, backports
jsonlite, xml2, data.table, testthat, knitr, rmarkdown, covr,
magrittr
jsonlite, xml2, testthat, knitr, rmarkdown, covr, magrittr