[Rd] The case for freezing CRAN

[Geoff Jentry]

On Thu, 20 Mar 2014, Dirk Eddelbuettel wrote:
> o Roger correctly notes that R scripts and packages are just one issue.
>   Compilers, libraries and the OS matter.  To me, the natural approach these
>   days would be to think of something based on Docker or Vagrant or (if you
>   must, VirtualBox).  The newer alternatives make snapshotting very cheap
>   (eg by using Linux LXC).  That approach reproduces a full environemnt as
>   best as we can while still ignoring the hardware layer (and some readers
>   may recall the infamous Pentium bug of two decades ago).

At one of my previous jobs we did effectively this (albeit in a lower tech 
fashion). Every project had its own environment, complete with the exact 
snapshot of R & packages used, etc. All scripts/code was kept in that 
environment in a versioned fashion such that at any point one could go to 
any stage of development of that paper/project's analysis and reproduce it 
exactly.

It was hugely inefficient in terms of storage, but it solved the problem 
we're discussing here. As you note, with the tools available today it'd be 
trivial to distribute that environment for people to reproduce results.