$ bb -Dmalli.registry/mode=strict
Babashka v1.12.194 REPL.
Use :repl/quit or :repl/exit to quit the REPL.
Clojure rocks, Bash reaches.

user=> (System/getProperty "malli.registry/mode")
"strict"
user=> (require 'malli.core)
nil
user=> (malli.registry/-schemas (malli.registry/custom-default-registry))
{}
user=>

$ clj -J-Dmalli.registry/mode=strict
Clojure 1.11.4
user=> (System/getProperty "malli.registry/mode")
"strict"
user=> (require 'malli.core)
nil
user=> (malli.registry/-schemas (malli.registry/custom-default-registry))
{}