A jar needs deps. A fat jar still often needs a script to run it with baked-in parameters, JAVA_HOME/PATH manipulation, maybe a tanuki service wrapper, a cron j

A jar needs deps. A fat jar still often needs a script to run it with baked-in parameters, JAVA_HOME/PATH manipulation, maybe a tanuki service wrapper, a cron job to keep it running, some what to bootstrap it from scratch (maven) - everything extremely specific to the java ecosystem. Docker can do some a lot of that stuff generically, then leveraging kubernetes you can get much more advanced deployments based on pods, labels, etc... at a much higher level, with a dashboard. Throw in Prometheus/ELK etc... then you have a centralized log store you can just read. If your entire stack is a monolithic fat jar, this isn't the solution you are looking for.