Writing and publishing a technical note about an R package
Obviously you will need to do a bit of work to find the most appropriate journal for your field, but publishing an article about an R package is completely acceptable. In fact, "An R package for reading EPANET files" by Eck was published in Environmental Modelling &amp; Software which describes itself as follows,


  Environmental Modelling &amp; Software publishes contributions, in the
  form of research articles, reviews and short communications, on recent
  advances in environmental modelling and/or software. The aim is to
  improve our capacity to represent, understand, predict or manage the
  behaviour of environmental systems at all practical scales, and to
  communicate those improvements to a wide scientific and professional
  audience.