Technically, the idea of the packr() function came from the package 'rmd', which can load and install a group of R markdown packages. As it is quite useful to load user-defined multiple packages, I decided to pack the skeleton of 'rmd' into packr()so that everyone can create rmd-like packages. I would prefer to developing them independently because I will tailor 'rmd' for some specific use, while the current version is universal and sufficient for users to develop their own packages.
Thanks a lot for your kind comments.