Designed and implemented a Puppet-based system for configuring and managing clusters of Solaris zones, interacting with F5 BIG-IP load balancers to serve application traffic from the pool of zones. This replaced a setup where larger servers were manually configured and each ran multiple applications, and scaling/failover was difficult.

Nowadays we'd have been looking at Kubernetes or similar, but at the time with a requirement for use of in-house Solaris zones and other solutions in their infancy, building our own Puppet setup made sense and has served us well for many years.