I think it's realistic to assume that most invocations will eventually end up in build.boot where you can pass regular data to tasks. Maybe for CLI experimentation it would be useful to still expose something so user can just provide a few args like '--plugin-opt-1 --plugin-opt-2'

But outside of that just have a config option that takes a map.

What I don't understand — would this replace tests.edn for boot users? If so maybe the right thing is just having a tests-edn option. This way the format is identical and documentation doesn't require adjustments based on build tool choice

(added this to the issue as well)

I'd like it to mimic as close as possible Kaocha on lein or clj, i.e. with a tests.edn, but most things in tests.edn can be overridden with command line flags.