HashiCorp Terraform allows to manage configuration of cloud resources or other sytems (REMOTE) in a declarative way. It defines how the desired state of the REMOTE is defined (HCL) and the workflow to apply it, but leaves it to plugins (terraform providers) to implement the interaction with each REMOTE.
Terraform is not FOSS. The Business Source License permits modification and redistribution, but not free usage by competitors of HashiCorp .