We use a setup where we have multiple repos with Terraform configuration and thus multiple Terraform states. We then use Terraform remote state to link everything together. I am talking about 10-20 repos and states. Orthogonal to that, we use multiple workspaces to describe the infra in different environments.

The problems I have personally experienced with this approach are:

- if you update one of the root Terraform states, you need to execute a Terraform apply for every repo that depends on that Terraform state; developers do not do that because either they forget or they do know but are too lazy and subsequently are surprised that things are broken

- if you use workspaces for maintaining the infra in different environments, and certain components are only needed in specific environments, then the Terraform code becomes pretty ugly (using count which makes a single thing suddenly a list of things, which you then have to account for in the outputs which becomes very verbose)

Is Terragrunt something that would help us? I do not know Terragrunt, and a quick look at the website did not make that clear for me.