Infrastructure as Code

Managing infrastructure through machine-readable definition files rather than manual configuration

Overview

Infrastructure as Code (IaC) is the practice of managing and provisioning infrastructure through code rather than manual processes. Instead of clicking through web consoles or running one-off commands, infrastructure is defined in version-controlled files that can be executed repeatedly to produce identical environments.

This approach treats infrastructure with the same rigor as application code: it’s versioned, reviewed, tested, and deployed through automated pipelines.

Why Infrastructure as Code?

The problem with manual infrastructure

Traditional infrastructure management faces several challenges:

  • Inconsistency: Manual steps vary between operators and environments
  • Undocumented: Critical knowledge exists only in operators’ heads
  • Error-Prone: Human mistakes during repetitive tasks
  • Slow: Manual provisioning takes hours or days
  • Untrackable: No audit trail of what changed, when, or why
  • Irreproducible: Difficulty recreating environments exactly

The IaC solution

Infrastructure as Code addresses these challenges by making infrastructure:

Declarative - Describe the desired state, not the steps to achieve it. The IaC tool handles the implementation details.

Versioned - Every infrastructure change is committed to Git, providing complete history and the ability to rollback.

Automated - Infrastructure deploys through pipelines without human intervention, eliminating manual errors.

Testable - Infrastructure changes can be validated before production deployment.

Documented - The code itself is the documentation, always current and accurate.

Reproducible - The same code produces identical infrastructure every time, across all environments.

Core Concepts

Declarative vs imperative

Imperative approaches specify the exact steps: “Create a server, then install software, then configure networking.”

Declarative approaches specify the desired outcome: “I need a server with this software and network configuration.” The IaC tool determines the necessary steps.

Most modern IaC tools use the declarative approach, making them more maintainable and resilient.

State Management

IaC tools maintain a “state” - a record of what infrastructure currently exists. When you change your code and re-run the tool, it compares the desired state (your code) with the actual state (what exists) and makes only the necessary changes.

This enables:

  • Drift detection - Identify manual changes made outside IaC
  • Safe updates - Modify only what changed
  • Dependency management - Update resources in the correct order

Idempotency

Running the same IaC code multiple times produces the same result. If infrastructure already matches the code, the tool makes no changes. This property is called idempotency and is essential for reliable automation.

Infrastructure as Code in EDP

The Edge Developer Platform uses IaC extensively:

Terraform and Terragrunt

Terraform is our primary IaC tool for provisioning cloud resources. We use Terragrunt as an orchestration layer to manage multiple Terraform modules and reduce code duplication.

Our implementation includes:

  • infra-catalogue - Reusable infrastructure components (modules, units, and stacks)
  • infra-deploy - Full environment definitions using catalogue components

Platform stacks

We organize infrastructure into stacks - coherent bundles of related components:

Each stack is defined as code, versioned independently, and can be deployed across different environments.

GitOps integration

Our IaC integrates with GitOps principles:

  1. All infrastructure definitions live in Git repositories
  2. Changes go through code review processes
  3. Automated pipelines deploy infrastructure
  4. ArgoCD continuously reconciles Kubernetes resources with Git state

This creates an auditable, automated, and reliable deployment process.

Benefits realized

Consistency across environments

Development, testing, and production environments are deployed from the same code. This eliminates the “works on my machine” problem at the infrastructure level.

Rapid environment provisioning

A complete EDP environment can be provisioned in minutes rather than days. This enables:

  • Quick disaster recovery
  • Easy creation of test environments
  • Fast onboarding for new team members

Reduced operational risk

Code review catches infrastructure errors before deployment. Automated testing validates changes. Version control enables instant rollback if problems occur.

Knowledge sharing

Infrastructure configuration is explicit and discoverable in code. New team members can understand the platform by reading the repository rather than shadowing experienced operators.

Compliance and auditability

Every infrastructure change is tracked in Git history with author, timestamp, and reason. This provides audit trails required for compliance and simplifies troubleshooting.

Getting started

To work with EDP’s Infrastructure as Code:

  1. Understand Terraform basics - Review Terraform documentation
  2. Explore infra-catalogue - Browse infra-catalogue to understand available components
  3. Review existing deployments - Examine infra-deploy to see how components are composed
  4. Follow the Terraform guide - See Terraform-based deployment for detailed instructions

Best Practices

Based on our experience building and operating IaC:

Version everything - All infrastructure code belongs in version control. No exceptions.

Keep it simple - Start with basic modules. Add abstraction only when duplication becomes painful.

Test before production - Deploy infrastructure changes to test environments first.

Use meaningful commit messages - Explain why changes were made, not just what changed.

Review all changes - Infrastructure changes should go through the same review process as application code.

Document assumptions - Use code comments to explain non-obvious decisions.

Manage secrets securely - Never commit credentials to version control. Use secret management tools.

Plan for drift - Regularly compare actual infrastructure with code state to detect manual changes.

Challenges and limitations

Infrastructure as Code is powerful but has challenges:

Learning curve - Teams need to learn IaC tools and practices. Initial productivity may decrease.

State management complexity - State files must be stored securely and accessed by multiple team members. State corruption can cause serious issues.

Provider limitations - Not all infrastructure can be managed as code. Some resources require manual configuration.

Breaking changes - Poorly written code can destroy infrastructure. Safeguards and testing are essential.

Tool lock-in - Switching IaC tools (e.g., Terraform to Pulumi) requires rewriting infrastructure code.

Despite these challenges, the benefits far outweigh the costs for any infrastructure of meaningful complexity.

Why we invest in IaC

The IPCEI-CIS Edge Developer Platform requires reliable, reproducible infrastructure. Manual provisioning cannot meet these requirements at scale.

By investing in Infrastructure as Code:

  • We can deploy complete environments consistently
  • Platform engineers can focus on improvement rather than repetitive tasks
  • Infrastructure changes are transparent and auditable
  • New team members can contribute confidently
  • Disaster recovery becomes routine rather than heroic

Our IaC tools (infra-catalogue and infra-deploy) embody these principles and enable the platform’s reliability.

Additional Resources

Terraform Ecosystem

Infrastructure as Code Concepts

EDP-Specific Resources

Terraform-based deployment of EDP

As-code definitions of EDP clusters, so they can be deployed reliably and consistently on OTC whenever needed.

Stacks

Platform-level component provisioning via Stacks