Frustration over not having a proper parametric polymorphism (Also known as “static generics”) so I cannot write elegant functional style code to promote more code reuse. You wonder how do you do some kind of Map/Filter/Reduce in Golang? Check out go-funk in Github but bear in mind they use reflection to emulate it so the performance can be very dissatisfying.

This is the biggest pain point of Go throughout my journey and I have been waiting so long for Go 2! PLEASE!