Error(s) in re-building vignettes:
--- re-building 'converting.Rmd' using rmarkdown
Quitting from lines 116-129 (converting.Rmd) 
Error: processing vignette 'converting.Rmd' failed with diagnostics:
there is no package called 'ggplot2'
--- failed re-building 'converting.Rmd'

--- re-building 'cpp11.Rmd' using rmarkdown
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
Warning in get_engine(options$engine) :
  Unknown language engine 'cpp11' (must be registered via knit_engines$set()).
--- finished re-building 'cpp11.Rmd'

--- re-building 'internals.Rmd' using rmarkdown
--- finished re-building 'internals.Rmd'

--- re-building 'motivations.Rmd' using rmarkdown
Quitting from lines 449-461 (motivations.Rmd) 
Error: processing vignette 'motivations.Rmd' failed with diagnostics:
there is no package called 'ggplot2'
--- failed re-building 'motivations.Rmd'

SUMMARY: processing the following files failed:
  'converting.Rmd' 'motivations.Rmd'

Error: Vignette re-building failed.
Execution halted