How does Gruntwork Pipelines work at a high level?

[zackproser]

A customer asked:

How does the automated build and deployment part work? If you are not using CodePipelines - what do you use to deploy Docker images and update Terraform through Gruntwork Pipelines?

[zackproser]

We have scripts that will make the relevant changes to Terraform code and then run plan or apply on the updated version.