Scaling Enterprise AWS Architecture from a Single Repository

Abstract Managing dozens of AWS accounts in a single Terraform repository often forces a risky, “one-size-fits-all” module versioning strategy, where a single core update can disrupt hundreds of stable production deployments.

This session delivers a blueprint for architectural flexibility. Learn how to leverage GitHub Actions and a custom Bash pre-processor to dynamically inject environment-specific module versions at runtime based on individual .tfvars files. We will demonstrate how to achieve safe, granular upgrades—keeping legacy environments pinned to stable releases while seamlessly onboarding new spokes to the latest features. Finally, we will pit this pipeline against Terraform Cloud (TFC) to analyze the tradeoffs between managed workspace governance and runtime version flexibility.

Key Takeaways: The Versioning Trap: Why centralized automation fails at scale and how to avoid monolithic dependency traps.

Runtime Injection: Using GitHub Actions and Bash to dynamically target module versions per environment.

GHA vs. TFC: A cold, hard look at when managed governance limits your deployment flexibility.

Target Audience: DevOps Engineers, Cloud Architects, and Platform Engineers scaling IaC on AWS.