Not to mention all the various in-house systems in the 2010-era. I worked at a small place back in 2013 that had built their own container platform about a year

Not to mention all the various in-house systems in the 2010-era. I worked at a small place back in 2013 that had built their own container platform about a year before Docker was released. It was more like workqueue than borg. But it worked well enough. Eventually we got tired of maintaining our own snowflake scheduler and switched to Kubernetes. But I'm also old enough to remember pre-borg systems used in HPC. Maui, TORQUE, etc. I wasn't surprised batch scheduling finally got used for service deployment.