What an excellent post! What I would add though, is that you can gain some simplicity by removing abstractions (e.g. interfaces) and sometimes it's just worth i

What an excellent post! What I would add though, is that you can gain some simplicity by removing abstractions (e.g. interfaces) and sometimes it's just worth it. For example, a good practice may be to abstract away all implementations and use interfaces instead, but for things like logger (which may be a bit complex to abstract depending on it's API), you may be just fine logging to some buffer instead of maintaining mocks (and in Go you'll probably make expectations what they should be called with). Focus on things that matter - if you want to check logs in your tests too, make it as effortless as it can be (e.g. use snapshots for those).