Combine PDFs on the command line with pdfunite

I often need a quick way to combine PDF pages into a single file. I've used macOS's Preview in the past but found it clunky so I went looking for a command line alternative.

There seem to be many ways to do this, but I've found the pdfunite utility to be the least friction method for me.

pdfunite file1.pdf file2.pdf destination.pdf

Files are combined in the order you supply them in the arguments.

Thankfully pdfunite is easily installable on macOS, as part of the Poppler project, using brew install poppler.