This blog post is a supplement to the West Michigan R User Group March 2020 Meeting.


You may have noticed that sometimes after upgrading to a new version of R, you need to install all of your packages again. This happens because the new install of R can’t find the location of the old packages. Even if it could, it would still be a good idea to rebuild all of your packages because packages are built for specific versions of R. So sometimes a package built for one version will need to be rebuilt for another. I’m leaving out a lot of details here, but that is the gist of it.

When I upgrade my version of R, many scripts will start breaking since R can’t find required packages on my system. Then I have to go track down which packages are missing in my new environment and install them manually. This can take a long time, especially on systems where you must compile from source. I would like to have all the same packages avialable to me that I had in my previous version so that everything just works out of the box. What is the best way to do that? I’m not sure, but I have whipped up a solution that has worked for me, although it has its flaws.

My Current-State Workflow

Since the majority of the packages that I use are from CRAN, I have written an R script that goes through a library location to identify and install CRAN packages while telling me which packages I will need to install from elsewhere (e.g., Bioconductor, Omegahat, github, internal and personal packages).

I still install non-CRAN pacakges manually, but it reduces the number of packages that I have to process considerably. Installing non-CRAN packages could be automated to a degree, but since packages are installed from so many different places, I have not seen the benefit.

Here are the simple steps that I use:

Finding the Library Path

Prior to installing a new version of R, I find out where my existing version of R is searching to find its packages. These are the locations that I will be coming back to in order to get a list of packages to build under my new version of R. To do that, I use the .libPaths() function.

In particular, the first element returned is my personal library (this may also be defined by the R_LIBS_USER environment variable). Unless you are a site administrator, that is likely where the packages you want will be. I take note of these locations, as I will need them in the next step.

After Upgrade

Now that I have the location to the user library of my prior installation, I’m ready to upgrade. Once I’ve have upgraded, I start an R session and source() this file:

The function install_packages_from_library() takes a vector of library paths to check and the dots (...) are passed to install.packages() so that I can pass custom parameters such as a CRAN mirror or specify building from source.

An example usage would be:


I get one or two prompts and then package installation commences.

Alternative Approaches

The internet is full of articles, blog posts, Stack Overflow answers, and forum posts on the subject.

A very popular answer seems to be to copy all packages from the old library directory to the new one and then run update.packages(ask = FALSE, checkBuilt = TRUE) (note the checkBuilt parameter, which will cause the function to upgrade packages built under a different version). This seems like a very rational and convenient solution that would work for most cases. However, a quick glance at the function documentation and source code indicates to me that it does not solve the problem of packages from non-standard sources. As a result, the update.packages() approach risks moving packages into your new R library that were built for the wrong version of R. Hence my reason for creating the script above.

I still think there must to be a better way. How can I automate installation of all packages in a library, not just CRAN packages? Also, is there a better way to standardize my environment across workstations? For example, what do I do when I move to a new machine which does not have access to those old package libraries?

Metapackage, or One Package to Install Them All

That got me thinking about the power of the packages themselves. Specifically, metapackages, or packages that install/invoke other packages. A popular metapackage that you probably already know is tidyverse. So why not a metapackage for personal use? Or even metapackages for specific use-cases?

With the Remotes field in a package DESCRIPTION file, even packages from non-standard sources can be installed automatically with devtools.

So with that, I have created my first metapackage.


There does not seem to be a clear consensus on exactly the right way to handle package migration between versions of R. My previous workflow has served me well, but I am looking forward to using my new metapackage in the future. We will soon see how fastidous I am about updating packages that I begin using more or removing those that fall by the wayside.

Open Forum

What is your strategy?