JSON. The protocol for front-end / back-end communication, as well as between the back-end
and plug-ins, is based on simple JSON messages. I considered binary formats, but the actual
improvement in performance would be completely in the noise. Using JSON considerably lowers
friction for developing plug-ins, as it’s available out of the box for most modern languages,
and there are plenty of the libraries available for the other ones.
4 years later:
The choice of JSON was controversial from the start. It did end up being a source of friction, but for surprising reasons.
For one, JSON in Swift is shockingly slow.
