CI/CD Pipelines for Infrastructure-as-Code Delivery

Stefano Franco

January 6, 2025 (updated)

Introduction

Infrastructure as Code (IaC) revolutionizes the way cloud environments are built, managed, and maintained. To achieve scalable, secure, and efficient IaC deployments, Continuous Integration/Continuous Deployment (CI/CD) pipelines play a critical role. This whitepaper explores how to set up CI/CD pipelines tailored for IaC delivery, highlighting best practices, recommended tools, and strategies to streamline the deployment process.

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Why Use CI/CD Pipelines for IaC?

CI/CD pipelines are essential for delivering Infrastructure as Code (IaC) efficiently, securely, and reliably. By automating the provisioning, updating, and maintenance of cloud infrastructure, pipelines create a structured and consistent deployment process.

Advantages of CI/CD Pipelines

1. Security:

   • CI/CD pipelines securely handle credentials and sensitive data, integrating with tools like AWS Secrets Manager, HashiCorp Vault, or OpenID Connect (OIDC).
   • Centralized deployment ensures that sensitive information is not exposed during manual processes or stored locally. Pipelines also enforce best practices like role-based access control (RBAC).

2. Reliability:

   • Pipelines automate deployments, ensuring consistent execution and reducing the risk of human error.
   • Built-in stages like terraform plan and validation steps catch issues before they are deployed to production environments.

3. Traceability:

   • CI/CD pipelines provide a clear audit trail for every change, detailing who initiated a deployment, what was changed, and when.
   • This is invaluable for compliance, debugging, and understanding the history of infrastructure changes.

4. Compliance:

   • Pipelines can enforce organizational and regulatory compliance by integrating tools like Open Policy Agent (OPA) or Sentinel.
   • They automatically validate infrastructure against predefined policies, such as enforcing encryption, tagging standards, and network restrictions, ensuring consistent adherence to governance requirements.
   • This reduces the risk of deploying non-compliant infrastructure and simplifies audits.

5. Single Source of Truth:

   • With CI/CD pipelines, the IaC configuration stored in version control (e.g. Git repositories) becomes the single source of truth.
   • All changes are deployed through the pipeline, ensuring consistency between the IaC configuration and the deployed infrastructure. This eliminates discrepancies caused by ad-hoc manual changes.

6. Drift Prevention:

   • Automated pipelines ensure that the infrastructure state remains consistent with the IaC configuration.
   • This prevents configuration drift, where the deployed environment deviates from the defined codebase due to unauthorized or manual changes.

7. Consistency Across Teams:

   • Pipelines enforce standardized workflows, ensuring that teams follow the same process regardless of the environment or team member involved.
   • This standardization simplifies onboarding and collaboration across multiple teams.

8. Scalability:

   • CI/CD pipelines simplify the management of complex, multi-account, and multi-region environments.
   • Modular workflows allow for incremental deployments, scaling with your organization’s growth.

9. Automation of Testing and Validation:

   • Pipelines integrate testing stages to validate IaC changes before they are deployed.
   • Examples include static code analysis, compliance checks, and terraform validate to catch errors early in the process.

10. Faster Rollbacks:

    • Pipelines enable automated rollbacks in case of deployment failures.
    • Version control integration ensures that you can revert to a previous, stable version of your IaC configuration seamlessly.

Why It Matters

By adopting CI/CD pipelines, organizations establish a secure, automated, and traceable framework for deploying IaC. This approach not only increases operational efficiency but also ensures that infrastructure remains aligned with the IaC configuration, reducing risk and simplifying management.

Whether you're building a small-scale project or managing a multi-account enterprise environment, CI/CD pipelines provide the foundation for scalable, secure, and compliant infrastructure delivery.

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Generic CI/CD Tools or Purpose-Built CI/CD Tools for IaC?

When setting up CI/CD pipelines for Infrastructure as Code (IaC), one of the first decisions to make is whether to use generic CI/CD tools or tools specifically built for infrastructure management. Both options have their advantages, but purpose-built tools often provide features that streamline and enhance IaC workflows.

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Generic CI/CD Tools

Generic CI/CD tools, such as GitHub Actions, GitLab CI/CD, Jenkins, and CircleCI, are versatile platforms designed to automate various software development tasks, including testing, building, and deploying applications. While they are not specifically designed for IaC, they can be adapted for this purpose with custom scripting and configurations.

Advantages of Generic Tools

• Familiarity: Often already used within organizations for application delivery, making adoption straightforward.
• Flexibility: Can be customized to handle a variety of workflows beyond IaC.
• Ecosystem Integration: Extensive plugins and integrations for non-IaC use cases. For example:
  • Jenkins: Large library of plugins, including Terraform-specific integrations.
  • GitHub Actions: Pre-built actions for IaC tools like Terraform and Pulumi.
  • CircleCI: A developer-friendly platform designed to handle IaC pipelines efficiently.

Challenges with Generic Tools

• Complex Configuration: Setting up state management, drift detection, and IaC-specific workflows often requires custom scripting.
• Lack of Native Features: Generic tools don’t natively handle IaC requirements like Terraform state management or policy enforcement.
• Limited Visibility: Debugging IaC-specific issues can be more challenging without dedicated dashboards or workflows.

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Purpose-Built CI/CD Tools for IaC

Tools like Spacelift, Terraform Cloud, Terramate, Scalr, and Env0 are designed specifically to cater to IaC workflows. These platforms include built-in features that address the unique challenges of infrastructure management.

Advantages of Purpose-Built Tools

1. State Management:

   • Native support for managing Terraform state files, including encryption and locking, eliminates the need for additional configuration.

2. Drift Detection:

   • Automatically monitors for changes made outside of IaC pipelines, helping ensure consistency between your code and deployed infrastructure.

3. Policy Enforcement:

   • Tools like Spacelift, Terraform Cloud, and Scalr integrate with policy-as-code frameworks (e.g. Open Policy Agent, Sentinel) to enforce compliance standards during deployments.

4. IaC-Specific Dashboards:

   • Purpose-built tools provide intuitive dashboards for tracking plans, applies, and runs, simplifying debugging and auditing.

5. Seamless Authentication:

   • Native support for secure authentication methods like OpenID Connect (OIDC), reducing the need to manage long-lived credentials.

6. Collaboration and Workflows:

   • Features like role-based access controls (RBAC), workspace isolation, and detailed logging simplify team collaboration on IaC projects.

Examples of Purpose-Built Tools

• Spacelift: Offers features like drift detection, policy-as-code integration, and built-in state management.
• Terraform Cloud: Provides a native experience for Terraform users, with remote state management, team collaboration, and cost estimation.
• Terramate: Enhances Terraform workflows with automation features like stack orchestration, dependency management, and code generation, enabling efficient and scalable multi-stack IaC management.
• Scalr: Enterprise-grade features for IaC governance, including hierarchical policy management and multi-cloud support.
• Env0: Focuses on collaborative IaC deployments, with support for multiple frameworks and cost management.

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Combination of Generic and Purpose-Built CI/CD Tools

Organizations often face the decision of choosing between generic and purpose-built CI/CD tools. However, these two approaches are not mutually exclusive. A hybrid approach combining both types of pipelines can offer the best of both worlds, leveraging the flexibility of generic tools alongside the specialized features of purpose-built platforms. Below are two effective combination strategies:

1. Infrastructure Deployment with Purpose-Built Pipelines, Workload Deployment with Generic Pipelines

In this approach, purpose-built CI/CD pipelines (e.g. Spacelift, Terraform Cloud) are used to manage infrastructure deployments, ensuring robust state management, policy enforcement, and drift detection. Meanwhile, generic CI/CD pipelines (e.g. GitHub Actions, Jenkins) handle application or workload deployments.

• Advantages:

  • Ensures infrastructure and workloads are managed with tools tailored to their specific requirements.
  • Segregates responsibilities, reducing complexity and potential conflicts between infrastructure and application workflows.

• Use Case:

  • Ideal for environments where infrastructure and workload changes are handled by different teams or require distinct deployment processes.

2. Code Validation with Generic Pipelines, Deployment with Purpose-Built Pipelines

This method utilizes generic CI/CD tools for pre-deployment validation tasks, such as code formatting, linting, and security checks, before handing over the deployment to purpose-built pipelines.

• Advantages:

  • Leverages the extensive ecosystem of generic tools for validation and testing.
  • Ensures deployments benefit from the advanced state management and policy enforcement of purpose-built tools.

• Use Case:

  • Suitable for organizations that prioritize rigorous pre-deployment validation or need to standardize validation workflows across both infrastructure and application pipelines.

tip

For effective pre-deployment validation, consider integrating the following tools into your Terraform workflow:

• TFLint: A Terraform linter to catch syntax issues and enforce best practices.
• Trivy: A security scanner for IaC configurations to detect vulnerabilities and misconfigurations.
• Terraform-Docs: Automatically generates and validates documentation for Terraform modules.
• Open Policy Agent (OPA): A policy-as-code engine for validating compliance and enforcing organizational policies.
• Infracost: Shows cloud cost estimates and FinOps best practices for Terraform.

These tools ensure code quality, security, and maintainability, creating a seamless handoff for deployment.

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Key Benefits of Combining CI/CD Tools

• Enhanced Flexibility: Combines the versatility of generic tools with the IaC-specific capabilities of purpose-built platforms.
• Optimized Workflows: Ensures that the right tool is used for the right task, maximizing efficiency and effectiveness.
• Streamlined Collaboration: Allows teams to adopt tools best suited to their roles, improving collaboration between infrastructure and application teams.
• Reduced Costs: Avoids overloading purpose-built tools with tasks better suited to generic platforms, optimizing resource utilization.

By adopting a hybrid approach, organizations can build CI/CD workflows that are tailored to their specific needs while maintaining consistency, security, and scalability.

tip

Many Git providers, such as GitHub and GitLab, already include integrated CI/CD tools. These can be leveraged for tasks like code checks, linting, and security validation. By combining these built-in tools with a purpose-built IaC platform (e.g. Spacelift), you can create powerful and cost-efficient pipelines tailored to your organization's needs.

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Which Should You Choose?

The decision depends on your organization’s needs:

• Generic CI/CD Tools Are Ideal When:

  • You’re already using them for application deployments and want a unified platform.
  • Your IaC requirements are simple and don’t need features like drift detection or policy enforcement.
  • Your team has the expertise to script and configure custom workflows for IaC.

• Purpose-Built Tools Are Best When:

  • You manage complex, multi-account environments that require robust state management and compliance checks.
  • Your team wants to minimize custom configurations and leverage built-in IaC workflows.
  • You have a central team (e.g. platform engineering team) responsible for infrastructure deployments.

• Combination of Tools Is Optimal When:

  • You want to split responsibilities, using purpose-built tools for infrastructure deployment and generic tools for workload deployments.
  • You need a streamlined workflow where generic tools handle pre-deployment tasks (e.g. code checks, linting, and validation) while purpose-built tools manage the actual deployment.
  • Your organization spans multiple teams with distinct responsibilities, requiring specialized tools tailored to their needs.

tip

When choosing a CI/CD tool, consider whether the tool itself can be managed with Infrastructure as Code (IaC). This ensures your pipeline configurations are version-controlled, easily reproducible, and aligned with your infrastructure management strategy.

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Recommendation

For most IaC-heavy workflows, purpose-built CI/CD tools offer significant advantages, reducing complexity while enhancing security and reliability. We at Nuvibit love Spacelift's unrivaled flexibility and advanced features tailored to infrastructure management.

Here’s why Spacelift stands out for us:

• Flexibility Across IaC Tools: Spacelift supports a wide range of IaC frameworks, including Terraform, OpenTofu, Pulumi, and more, making it ideal for diverse environments.
• Native OPA Integration: With built-in support for Open Policy Agent (OPA), Spacelift simplifies policy enforcement, ensuring compliance and governance from day one.
• Streamlined Workflows: Spacelift excels in managing complex workflows, such as multi-account AWS environments or intricate state management, reducing operational overhead.
• Seamless Integration with NTC: Spacelift provides amazing synergies with Nuvibit Terraform Collection (NTC), enabling you to build robust, compliant, and secure AWS platforms effortlessly.

For organizations aiming to unlock the full potential of AWS, the combination of Spacelift and NTC provides the ultimate solution.

note

Due to Spacelift's exceptional value and perfect alignment with NTC, Nuvibit has partnered with Spacelift to maximize and enhance our synergies. As a certified partner with deep expertise in complex Spacelift implementations, Nuvibit is uniquely positioned to deliver best-in-class solutions.

tip

NTC also offers a Spacelift administration building block, making it extremely easy to set up and manage Spacelift environments alongside your AWS infrastructure. This integration reduces setup time and streamlines day-to-day operations.

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Authentication Strategies for CI/CD Pipelines

Proper authentication is critical for securely deploying IaC. Two primary methods are widely used:

1. OpenID Connect (OIDC)

OIDC provides short-lived tokens for pipeline authentication, eliminating the need for static credentials. AWS supports OIDC for CI/CD tools like GitHub Actions, GitLab, and Spacelift.

• Advantages:
  • Secure, short-lived tokens reduce credential exposure.
  • Simplifies credential management by linking directly to the identity provider.
• Configuration:
  • Set up an OIDC identity provider in AWS.
  • Assign roles with specific permissions to pipelines.
  • Link pipelines to OIDC for secure authentication.
• Learn more about AWS OIDC setup.

2. IAM Access Keys (Legacy Alternative)

Static IAM access keys can be used but are less secure and require regular rotation.

• Recommendations:
  • Limit permissions attached to the IAM user.
  • Use dedicated users for each pipeline to maintain accountability.
  • Rotate keys frequently and automate key expiration.

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Types of CI/CD Pipelines for IaC Delivery

Choosing the right pipeline architecture depends on the size and complexity of your infrastructure. Below are three recommended approaches:

1. Single Pipeline Deploying into a Single AWS Account (Default Approach)

• Description: A dedicated pipeline for each AWS account, typically linked to a specific IaC repository.
• Advantages:
  • Minimizes blast radius; changes affect only one account.
  • Easier state management with reduced dependency conflicts.
  • Simplifies troubleshooting and accountability.
• Use Case: This approach should be the standard way to deploy infrastructure, as it minimizes the blast radius between accounts and stages.

2. Multiple Pipelines Deploying into a Single AWS Account

• Description: Splits IaC deployment into multiple pipelines for the same account, separating infrastructure by logical components (e.g. networking, security, compute).
• Advantages:
  • Isolates Terraform state files, reducing dependency conflicts.
  • Facilitates incremental deployments and parallel workflows.
• Use Case: Useful for large, complex accounts with many distinct IaC resources to minimizes the blast radius in the account.

3. Single Pipeline Deploying into Multiple AWS Accounts

• Description: A single pipeline manages deployments across multiple AWS accounts.
• Advantages:
  • Centralized management for small-scale environments.
• Disadvantages:
  • Increases blast radius; changes can inadvertently affect multiple accounts.
  • More complex to maintain and troubleshoot.
• Use Case: Use only for uncritical infrastructure. Cross-account deployments have the biggest blast radius and risk.

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Naming Strategy Recommendations

Adopting a consistent naming convention simplifies pipeline management, provides clarity, and enhances traceability across infrastructure and application deployments. A thoughtful naming strategy becomes even more critical in environments with multiple AWS accounts and complex CI/CD workflows.

Separate Infrastructure and Application Deployments

It is highly recommended to separate infrastructure and application deployments into distinct pipelines and repositories. This separation offers several advantages:

1. Improved Governance: Different teams or roles can manage infrastructure and application independently, reducing cross-impact risks.
2. Simplified Maintenance: Updates to infrastructure components, such as networking or IAM configurations, are isolated from application deployments, minimizing potential disruptions.
3. Enhanced Security: Permissions can be tailored to the specific needs of infrastructure or application pipelines, reducing the attack surface.
4. Different Workflows: Infrastructure and application deployments usually require different pipeline workflows, allowing for optimized processes tailored to each domain.

tip

For applications, maintain a single repository and pipeline across environments while linking to infrastructure pipelines that handle environment-specific resources.

AWS Account Naming

Account names should reflect their purpose, environment, or stage to ensure clarity and traceability.

• Format: {prefix}-{application}-{environment} or {prefix}-{core-account-name}
• Examples:
  • aws-webshop-prod (AWS Production environment for Webshop App)
  • aws-webshop-dev (AWS Development environment for Webshop App)
  • aws-log-archive (AWS Centralized logging and audit account)
  • aws-connectivity (AWS Centralized networking account)

Pipeline Naming

Pipelines should clearly indicate whether they handle infrastructure or application deployment and align with the associated AWS account. This separation ensures better organization, minimizes confusion, and allows for more granular access controls.

• Infrastructure Repository Format: {prefix}-{account-name}
  • Use a prefix like infra- for infrastructure pipelines for easy differentiation between infrastructure and application pipelines.
• Application Repository Format: {prefix}-{application}
• Examples:
  • infra-aws-webshop-prod (Pipeline for provisioning infrastructure in the production environment of Webshop App)
  • app-webshop (Pipeline for deploying application code, typically tied to the application repository)

Repository Naming

Repository names should match the pipeline or resource they represent, maintaining alignment with the account and purpose. Since applications often have a single repository, while infrastructure is split across stages or environments, the naming convention reflects this:

• Infrastructure Repository Format: {prefix}-{application}-{environment} or {prefix}-{core-account-name}
• Application Repository Format: {application}
• Examples:
  • infra-aws-connectivity (IaC repository for the centralized networking account)
  • infra-aws-webshop-prod (IaC repository for the production environment)
  • infra-aws-webshop-dev (IaC repository for the development environment)
  • webshop (Single repository for application code, independent of the environment)

By aligning AWS accounts, pipelines, and repositories with a consistent naming strategy, organizations can streamline CI/CD workflows, simplify onboarding for new team members, and improve operational efficiency.

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Best Practices for CI/CD Pipelines with IaC

1. Implement Least Privilege:

   • Limit pipeline permissions to only those necessary for the deployment.
   • Use separate roles for production and non-production environments.

2. Automate State Management:

   • Use state backends like AWS S3 with DynamoDB locking or native state management from Spacelift or Terraform Cloud.
   • Protect state files with encryption and access controls.

3. Enable Drift Detection:

   • Monitor for changes made outside the pipeline to prevent configuration mismatches.

4. Implement Testing:

   • Incorporate plan checks, linting, and unit tests to catch issues before deployment.

5. Secure Secrets:

   • Store sensitive information (e.g. keys, tokens) securely using tools like AWS Secrets Manager or HashiCorp Vault.

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Conclusion

Setting up CI/CD pipelines for IaC deployments ensures a secure, scalable, and efficient infrastructure delivery process. Purpose-built CI/CD tools like Spacelift and Terraform Cloud enhance workflows, while proper authentication strategies such as OIDC minimize security risks. By adhering to best practices and adopting a modular pipeline architecture, you can significantly improve the reliability, security, and traceability of your IaC deployments.

For additional resources, explore the Nuvibit Building Blocks and start optimizing your AWS infrastructure today.