I have used HashiCorp's vagrant and terraform to build, test and deploy infrastructure as code. Review collected by and hosted on G2.com.
The fact that the opensource versions of their products are full products. They have found that fine line that allows one to have a viable business model without compromising by cutting down the features of their opensource product. Review collected by and hosted on G2.com.
We use hashicorp terraform and Vault in our infra to deploy cloud resources and to manage secret in our environment, terraform and vault integrates very well and using both the need of CICD can be removed till some extent. Review collected by and hosted on G2.com.
The fast feedback and listening to it's customer request, terraform is the defacto for IAAS Review collected by and hosted on G2.com.