Fluency in bug fixing looks like, "there was an unhandled concurrency error on write in the message importing service therefore I will implement a retry from th

Fluency in bug fixing looks like, "there was an unhandled concurrency error on write in the message importing service therefore I will implement a retry from the point of loading the message" and then you just do that. There are only a few appropriate ways to handle concurrency errors so once you have done it a few times, you are just picking the pattern that fits this particular case. One might say, "yes but if you see so many concurrency related bugs, what is the root cause and why don't you do that?" And sometimes the answer is just, "I work on a codebase that is 20 years old with hundreds of services and each one needs to have appropriate error handling on a case by case basis to suit the specific service so the root cause fix is going and doing that 100 times."