Ecosystem & Integrations – Terraform Cloud vs. Spacelift vs. Scalr

When managing Infrastructure as Code (IaC), the core functionality of a platform is crucial, but its ecosystem and ability to integrate with your existing tools and workflows are equally important. A rich set of integrations streamlines operations, enhances automation, and improves collaboration. This post provides a matter-of-fact comparison of the ecosystem and integration capabilities of three prominent IaC management platforms: Terraform Cloud, Spacelift, and Scalr, with a closer look at how Scalr stands out.

VCS Integration & GitOps Workflow

A cornerstone of modern IaC is tight integration with Version Control Systems (VCS) to enable robust GitOps workflows.

• Terraform Cloud offers integrations with popular VCS providers like GitHub, GitLab, Bitbucket, and Azure DevOps. It supports VCS-driven workspaces, automatically triggering runs based on commits and pull requests. Terraform Cloud provides feedback within the VCS on run status.
• Spacelift also provides strong VCS integration with GitHub, GitLab, Bitbucket, and Azure DevOps. It is designed with a GitOps-native approach, supporting various Git flows and leveraging Git provider APIs, such as GitHub Checks and Deployments, for enhanced visibility. It triggers runs on code changes and offers PR commentary.
• Scalr delivers strong VCS integration with GitHub, GitLab, Bitbucket, and Azure DevOps. Its VCS-driven workspaces trigger runs on commits and pull requests. A key differentiator for Scalr is its in-depth PR comments, which summarize the run and post detailed logs directly in the PR upon failure. Furthermore, Scalr uniquely offers the option to execute runs (both plan and apply) directly from PR comments, providing an Atlantis-style workflow that enhances developer productivity and streamlines the review process.

Policy as Code & Security Integrations

Ensuring compliance and security is paramount. Policy as Code (PaC) integrations are vital for enforcing standards.

• Terraform Cloud primarily uses Sentinel, its proprietary policy-as-code framework. It also offers integration with Open Policy Agent (OPA) through run tasks, and has been expanding its native OPA support.
• Spacelift provides native OPA integration, allowing users to define policies for various aspects of their workflows, including planning, applying, and task execution. It supports policy evaluation at multiple points in the CI/CD pipeline.
• Scalr offers native OPA integration for robust policy enforcement. Critically, Scalr also includes native Checkov integration. This built-in static analysis for infrastructure misconfigurations directly within the pipeline, before terraform init, provides an early and automated layer of security and compliance checking without requiring custom setup.

Observability, Notifications & Monitoring

Visibility into IaC operations and timely notifications are essential for operational excellence.

• Terraform Cloud provides notifications for run events via Slack and webhooks. It also offers an integration with Splunk for log aggregation.
• Spacelift integrates with Datadog for monitoring and provides notifications through various channels including Slack and Microsoft Teams via webhooks. It maintains detailed audit trails for all operations.
• Scalr offers a comprehensive suite of observability integrations, including Datadog, AWS EventBridge, Slack, and Microsoft Teams. The AWS EventBridge integration allows for building sophisticated event-driven automation. Additionally, Scalr supports OpenMetrics, enabling users to pull metrics into their preferred monitoring solutions, offering greater flexibility in how they observe their IaC processes.

Extensibility & Customization

The ability to extend the platform and integrate custom tooling is crucial for adapting to specific organizational needs.

• Terraform Cloud allows for custom integrations primarily through its API and "Run Tasks," which can trigger external tools at specific points in a run lifecycle.
• Spacelift is highly extensible, supporting custom inputs, lifecycle hooks, and the ability to bring your own runner image for maximum flexibility. It offers an API and a Terraform Provider to manage Spacelift resources. Spacelift also supports a broad range of IaC tools beyond Terraform, including Pulumi, CloudFormation, Kubernetes, Ansible, and Terragrunt.
• Scalr provides custom hooks that allow for the integration of arbitrary tools into the workflow at various stages. It features a comprehensive API and a dedicated Terraform Provider for managing Scalr itself, enabling true "infrastructure as code" for your IaC platform. This allows for programmatic configuration and management of Scalr environments, workspaces, and other resources.

Module Management & Other Key Integrations

Efficiently managing and utilizing Terraform modules, along with other essential tools, enhances productivity and governance.

• Terraform Cloud features public and private module registries for sharing and versioning modules within an organization. It also offers cost estimation features.
• Spacelift allows users to test modules as part of their workflow and integrates with Infracost for cost estimation. It also supports Terragrunt.
• Scalr features both global and environment-level module registries, providing granular control over module usage and versions. A significant advantage is Scalr's native integration with Infracost for transparent cost estimation directly within the UI based on Terraform plans. Scalr also integrates seamlessly with Dependabot to automatically check for updates to Terraform modules stored in Scalr and create PRs for updates, ensuring modules stay current. Furthermore, Scalr has excellent Terragrunt support, catering to teams that leverage Terragrunt for managing their Terraform configurations.

Conclusion

Choosing the right IaC management platform requires careful consideration of its integration capabilities and how well it fits into your broader DevOps toolchain.

Terraform Cloud provides a solid foundation with core VCS integrations and its Sentinel policy framework, along with an expanding set of run task integrations.

Spacelift offers a flexible, GitOps-native platform with strong OPA support, extensibility through custom runners, and broad IaC tool compatibility.

When comparing ecosystems, Scalr presents a compelling and comprehensive offering. Its Atlantis-style PR-based execution, native integrations with OPA and Checkov for proactive security, broad observability through Datadog, AWS EventBridge, Slack, MS Teams, and OpenMetrics, and robust module management with Dependabot integration provide a deeply integrated and efficient experience. The ability to manage Scalr itself via a Terraform Provider further underscores its commitment to IaC principles. These features, combined with custom hooks and native Terragrunt and Infracost support, position Scalr as a strong contender for organizations seeking a powerful, well-integrated, and developer-friendly IaC management solution.