factor out the code to cat not-OK lines from check logs, and incrementally print the logs in case of >= 10 minutes
consider BioC packages
factor out strsplit()
exclude some known broken packages in the `exclude` field, e.g. localsolver
try rstudio mirror first, then cran main site
download from Github can fail, so try 5 times
DLMtool seems to be time-consuming as well
silence
add more recipes