UPDATE: Implemented VERT_USE_EXTERNAL_TOOLS environment variable. See #Configuration.

I had passed the filter parameter as "data", which should help prevent most issues with it but yes I agree that it would’ve been better to use external tools to do the heavy-lifting. I avoided them to make the program cross-platform and easier to setup (you currently can just run a simple pip command to install it). I may introduce them as optional backends later with a warning on the default ones but for now I’m postponing it.