Doesn't always mean it's particularly performant, unfortunately. The JSON lib in PHP is still C (part of Zend), but it's very susceptible to malloc failures (one big contiguous request for the whole shebang), and it's generally way faster to serialize arrays into a .PHP file you load than into JSON if you're storing it locally. I compared what I read there to the serde stuff for rust and the difference is stark.

Maybe having most of this stuff in c libs with scripts wrapped around them will make it easier to migrate. Keep the same py but swap out the lib from C to some rust that's still useful in a crate for pure rust projects.