Something to note here is that everything is known and done statically in the source code. This could be addressed through metaprogramming if only the Go language had some ^^

We have similar needs at Sqreen but for security monitoring and protection reasons: we need to dynamically instrument functions at run time, while not asking any code modification to our users. To do so, we instead leverage the Go compiler to perform compile-time instrumentation that inserts hooks anywhere interesting. You can read more about this approach at https://blog.sqreen.com/dynamic-instrumentation-go/