Inkscape's format is just SVG, so any tool that can do SVG-PDF will do. I've seen cairosvg, imagemagick and rsvg used for this, but if your deployment allows, it does make the most sense to use inkscape from the CLI to avoid any inconsistencies:

    $ inkscape rendered.svg --export-pdf=output.pdf

I think there's also a way to do batch processing where you don't need to spin up a new inkscape process for each file (which takes time), but I don't remember how it works anymore.