Puppet
Puppet is an open-source configuration management tool that automates the provisioning, configuration, and management of IT infrastructure. It uses a declarative language to define the desired state of systems, ensuring consistency across servers, applications, and networks. It is widely used for infrastructure as code (IaC) and DevOps practices to streamline deployment and maintenance.
Developers should learn Puppet when managing large-scale, heterogeneous IT environments that require automated configuration and compliance, such as in cloud deployments, data centers, or multi-server applications. It is particularly valuable for ensuring system consistency, reducing manual errors, and enabling repeatable infrastructure setups in DevOps workflows.