I just wrote a post on refactoring some Go code to use interfaces. I outline the steps used to refactor this particular pattern: dev.to/chuck_ha/interfaces-in-go-3onc
I would also suggest reading sandimetz.com/99bottles/. It's a fantastic book that refactors code throughout the book and explains how to get there.
We’re a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.