Comment by cpx86

One big challenge I've found is the balance between standardization vs autonomy. E.g. monitoring, log formats, deployment, service discovery, etc are things that can benefit from being standardized across all services, but implementing it can be tricky. Too much autonomy and you end up reinventing the wheel (inevitably with variations) - too much standardization (e.g. by providing centralized libraries) can make development slower and create dependency hell.