[dpackard]

CloudTrail + Lambda is a good way to create automations in AWS! Great idea for a future setup option, especially for companies that don't use GitHub.

Here are some reasons we think GitHub + Terraform IaaC is a good approach:

1. One benefit of doing tagging in the infrastructure as code is that it creates visibility for engineering teams that use the IaaC as source of truth.

2. In our experience GitHub provides a natural segmentation for how resources could be tagged - it creates an efficient mapping of your tagging to resources based on being part of different GitHub repos.

3. CloudTrail is AWS specific. In the future we plan on expanding integration to Azure and GCP which would allow consistent tagging across all clouds from this centralized Catalog. We created a developer API to fetch the tagging which could be referenced in the Lambda you're referencing.