Infrastructure as Code: Benefits, Risks and Implementation Best Practices
Infrastructure as code explained: benefits, tools (Terraform, OpenTofu, CloudFormation, Bicep, Pulumi), state, reviews, drift, secrets and adoption.
What is infrastructure as code and how do you adopt it?
Infrastructure as code (IaC) defines cloud resources in version-controlled files that tools apply automatically. Adopt it by choosing one tool, storing state securely, organising code into reusable modules per environment, reviewing plans in pull requests, applying changes through CI rather than laptops, keeping secrets out of code, and checking for drift. The benefits are repeatability, review and recovery; the risks are mostly about state, permissions and accidental deletion.
This guide is for engineering leads and developers. It is a deep dive from DevOps for growing businesses.
Key takeaways
- Pick one tool per cloud and standardise.
- Remote, locked, encrypted, backed-up state.
- Review plans before apply; apply from CI.
- No secrets in code or plain-text state where avoidable.
- Detect and resolve drift.
- Protect critical resources from deletion.
Benefits
- Rebuild environments after incidents or for new regions.
- Consistent staging and production.
- Peer review and history for every infrastructure change.
- Security and cost policies checked automatically.
- Faster, documented onboarding for new engineers.
Tools
| Tool | Approach | Notes |
|---|---|---|
| Terraform | Declarative HCL, many providers | Widely used; licensed under the Business Source Licence since 2023 (HashiCorp) |
| OpenTofu | Open-source fork of Terraform | Community-governed (OpenTofu) |
| AWS CloudFormation / CDK | AWS-native templates or code | Deep AWS integration |
| Azure Bicep | Azure-native declarative language | Deep Azure integration |
| Pulumi | General-purpose languages | Familiar to application developers |
Practices that matter
- State: remote backend with locking, encryption, access control and versioning.
- Structure: modules for repeated patterns; separate state per environment and per major component to limit blast radius.
- Review: run a plan in CI on every pull request and require approval for production.
- Apply: from CI with short-lived credentials, not from developer laptops.
- Policy: automated checks for public exposure, encryption, tagging and cost.
- Protection: deletion protection on databases and critical storage; review any plan that destroys resources.
- Drift: scheduled plans that alert on differences.
Secrets and security
Do not put passwords or keys in IaC files. Reference a secret store, generate secrets inside the cloud provider, and treat state as sensitive because some resources write secret values into it. Give the CI role only the permissions it needs. See secrets management and cloud security posture reviews.
Adopting IaC step by step
- Choose a tool and a remote state backend.
- Import the most critical existing resources: network, database, production compute, DNS.
- Set up CI to plan on pull requests and apply on merge with approval.
- Recreate staging from code to prove it works.
- Add policy checks and drift detection.
- Stop console changes in production except for emergencies, and record them.
Hypothetical example: rebuilding staging
This example is hypothetical. A small product team had built its AWS environment by hand. When it needed a staging environment, nobody could reproduce production exactly. The team imported the VPC, database, containers and DNS into OpenTofu modules with remote encrypted state, set CI to post plans on pull requests, and created staging from the same modules with smaller sizes. A later accidental console change was caught by the nightly drift check.
Common mistakes
- Local state files on laptops.
- One huge state for everything.
- Applying without reviewing the plan.
- Secrets committed in variables files.
- Allowing console changes that never reach code.
Related guides
- Kubernetes vs serverless vs VMs for choosing a platform.
- Zero-downtime deployments for releasing applications.
- Business continuity for digital products for recovery planning.
- Cloud cost optimisation for tagging and policies.
Conclusion
Infrastructure as code makes environments reproducible, reviewable and recoverable. Choose one tool, protect state and secrets, review plans in CI, guard against destructive changes and watch for drift. Start with the resources you could least afford to rebuild by hand.
Building infrastructure for a new product?
ZSpace Labs is an India-based, remote-first technology studio working with Australian and international businesses on web applications and the infrastructure they run on. We do not offer managed cloud operations, but we set up reproducible environments for the software we build.
Common questions.
Defining cloud and server infrastructure, such as networks, databases, compute, permissions and DNS, in version-controlled files that tools use to create and update resources, instead of configuring them by hand in a console.