Scaling and Slicing PDF Documents with pdfjam and mutool

I recently encountered the following challenge: I had a PDF document consisting of multiple A4 pages, each of which I needed to print scaled up to A2. However, I only had an A4 printer available, and the printer driver was not able to perform the scaling and/or slicing on its own.

After a long search, and lots of disappointments (since neither of Libre Office, Inkscape and Evince could do what I wanted, or I simply couldn't find the feature), I came up with the following solution:

$ pdfjam -o scaled.pdf --a2paper input.pdf
$ mutool poster -x 2 -y 2 scaled.pdf sliced.pdf

The first command takes the input file, scales it up to A2 size, and writes it to an intermediate file. The second command slices each page from the intermediate file into 2 slices both vertically and horizontally, totaling in 4 slices per page, which again results in A4-sized slices the printer can print.