I think you have to work with the language you're in. I had similar frustrations when I first moved into doing some dev in Java and C# and it really bugged me that there was no compile-time guarantee that an Object reference passed as a method parameter would not be modified within that method (as I was so used to using const-refs with in C++)

In retrospect however, I was frustrated with these languages because I was wanting it to be something it wasn't. To my mind, the loss of that feature meant that programs were less expressive - particularly in large codebases - I had to read methods to work out if something was being modified or not.

To complain here about Go lacking immutability and constness features seems to be the same as complaining that it is missing in Python, Ruby or JavaScript. It's a fact that constness isn't a feature of these languages, if you want these features, use a different language.