Kusion vs Terragrunt

Kusion is a free, open-source platform orchestrator for internal developer platforms. Its AppConfiguration lets developers describe application workloads and resource dependencies without setting environment-specific values. The declarative model combines workload, accessory, pipeline, and dependency concepts. The documented process moves through Write, Generate, and Apply, with a three-way diff preview before changes are applied. Kusion currently applies operations to Kubernetes, Terraform, and on-premises infrastructure. Platform engineers can create reusable modules to standardize deployments and support developer self-service. A built-in delivery pipeline can be extended with customized plugin steps managed by platform owners. The project describes security and compliance support through base models, policy-as-code guardrails, and automatic injection of accessory secrets into workloads. External secret-store guides cover AWS, Alibaba Cloud, and Viettel Cloud. Kusion is a lightweight client-side solution with APIs for integration and automation. Its CLI installation methods cover macOS, Linux, and Windows. The project calls itself early and rapidly iterated; help and feedback are available through Slack or GitHub issues.

Terragrunt is an open-source infrastructure-as-code orchestration tool for running Terraform and OpenTofu at scale. It organizes infrastructure into independently operated units and groups related units into stacks. Its Run Queue uses dependency relationships to order operations and allow safe concurrency where possible. Teams can define shared backend settings, provider configuration, module inputs, and environment conventions once, then inherit them across units. It supports AWS, Google Cloud, Microsoft Azure, and other Terraform- or OpenTofu-supported platforms, with self-hosted state management and the ability to import existing resources. The core tool is documented for Windows, macOS, and Linux. The Free Scale tier allows up to 25 infrastructure units, unlimited runs, and unlimited resources without RUM, with community support and no credit card required. Team costs $500 a month, reflecting a 17% annual contract discount, and includes 200 infrastructure units and standard support. Terragrunt Scale adds CI/CD pipelines, drift detection, and automated dependency updates, with GitHub and GitLab workflow support. Enterprise has custom pricing.