The splitting part was easy enough with [officer](https://github.com/davidgohel/officer) but there aren't much options for putting them back together. I found some VBA scripts (none of which I want to use), and a [perl/js script](https://github.com/adamkewley/ppt-combiner-console/blob/master/pptCombiner.js) which only works on Windows and seems pretty fragile.

Are there any command line tools that could do this?