Refactor a Tangled Terraform Repo for a Multi-Account AWS Estate
Overview
What this challenge is about.
Audit a tangled Terraform repo, design a Terragrunt layout, migrate two AWS slices without destruction, and earn a verifiable certificate.
The scenario
The company is a financial-technology lender serving small and medium-sized businesses in the Netherlands; its platform team of a handful of engineers owns all cloud infrastructure across a regulated, multi-account AWS estate where downtime directly interrupts customer lending decisions.
The Brief
What you'll do, and what you'll demonstrate.
Refactor an 11,000-line Terraform monorepo into a layered, Terragrunt-composed structure by safely migrating two representative slices and documenting a path the team can follow for the rest.
Earning criteria — what you'll demonstrate
- Analyze a large, tangled Terraform codebase and produce an accurate cross-account dependency map
- Design a layered account/region/environment architecture and justify it against concrete operational pain
- Execute state migrations with `terraform state mv` and import so existing resources are preserved, not recreated
- Apply Terragrunt to remove duplicated configuration while keeping state isolation intact
- Document a migration so a team can continue it independently and de-risk a large refactor
Program Fit
Where this fits in your program.
Sharpens the same skills your degree expects you to demonstrate.
Aligned coursework coming soon.
Skills
Skills you'll demonstrate.
Each one shows up on your verified credential.
- Terraform
Apply terraform to solve real industry problems and demonstrate production-level capability.
- Terragrunt
Apply terragrunt to solve real industry problems and demonstrate production-level capability.
- Infrastructure As Code
Apply infrastructure as code to solve real industry problems and demonstrate production-level capability.
- State Migration
Apply state migration to solve real industry problems and demonstrate production-level capability.
- Iac Refactoring
Apply iac refactoring to solve real industry problems and demonstrate production-level capability.
- Platform Engineering
Apply platform engineering to solve real industry problems and demonstrate production-level capability.
Careers
Career paths this challenge builds toward
Completing this challenge demonstrates skills that transfer directly to these roles:
Platform Engineer
Mirrors the daily reality of owning shared infrastructure-as-code: untangling legacy Terraform, designing reusable module layers, and rolling out changes without disrupting teams that depend on the platform.
This challenge sharpens
- terraform
- iac-refactoring
- platform-engineering
Infrastructure / DevOps Engineer
Builds the exact muscle this role demands — safe state migrations, multi-account AWS structure, and Terragrunt composition — so you can evolve a growing cloud estate without recreating live resources or freezing delivery.
This challenge sharpens
- terragrunt
- state-migration
- infrastructure-as-code
Site Reliability Engineer
Reframes a risky refactor as a reliability problem: reducing drift, shrinking plan times, and documenting revertible change procedures so a small team can operate a regulated estate with confidence.
This challenge sharpens
- state-migration
- platform-engineering
- iac-refactoring