Wire
Compile-time dependency injection for Go
...Because Wire operates without runtime state or reflection, code written to be used with Wire is useful even for hand-written initialization. Dependency injection is a standard technique for producing flexible and loosely coupled code, by explicitly providing components with all of the dependencies they need to work. In Go, this often takes the form of passing dependencies to constructors. Dependency injection tools like Wire aim to simplify the management of initialization code. You describe your services and their dependencies, either as code or as configuration, then Wire processes the resulting graph to figure out ordering and how to pass each service what it needs.