ruby-pdns is a simple framework to develop dynamic DNS records using the Ruby language hosted in a PowerDNS Pipe Backend. The framework abstracts the complexities of coding custom records away from the developer, enabling you to focus on the task.
ogslb is a PowerDNS backend designed to perform global server load balancing using round-robin DNS. It can take into account health/performance to balance requests across multiple destinations. Health is determined using user-created Python scripts.