On: Understanding Jane Street

[mgaunard]

That is not the idiomatic way to use OCaml, so I wouldn't assume they do that.

[SonOfLilit → mgaunard]

At least in similar languages like Haskell, what you do is let the compiler infer types and then press an IDE key combination to write out those inferred types as part of your code so you would get an error if you ever accidentally change the types.

[LeonidasXIV → mgaunard]

Writing `mli` files is pretty much idiomatic or at the very least, not unusual.

[mgaunard → LeonidasXIV]

Only for the public API boundary.