Pulumi vs. Chef, Puppet, etc.
Chef, Puppet, Ansible, and Salt are all popular configuration management tools. These tools help you install and manage software on existing cloud infrastructure, either for bootstrapping a virtual machine, or patching one. They do not attempt to solve the problem of provisioning or updating infrastructure, containers, or serverless resources.
Pulumi is fundamentally different than these tools and works great alongside them. Pulumi manages provisioning and updating of your cloud infrastructure and applications, including virtual machines, containers, databases, hosted cloud services, and serverless functions.
Pulumi uses expressive, general-purpose languages, much like some configuration management tools, to define cloud requirements and desired infrastructure state. The Pulumi tool then takes these descriptions and can manage multiple environments to ensure that your infrastructure is always up to date, either through its CLI or in a hosted CI/CD scenario.
Pulumi works well with modern “immutable infrastructure” architectures, where bootstrapping and patching are unnecessary. In such cases, configuration management is not needed in the usual sense. Pulumi also works well with classical approaches to infrastructure, however, which often entail virtual machines and where continuing to use a configuration tool in conjunction is easy. In either case, Pulumi will help on your path to cloud native architectures.