[Julio-Guerra]

We haven't modified the compiler but instead plugged into it an external instrumentation tool using the compiler option `-toolexec`.

With this option, the compiler invokes every toolchain binary (compile, asm, link, etc.) through the provided program. So you can basically write a proxy program intercepting calls to `compile` to do source-code instrumentation, exactly like you would with go generate, but now automatically done during compilation on every package.

[gobwas]

Ah, cool! Thank you so much, didn't know about this parameter :D Will try it definitely.