Kusion vs Spacelift

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.

Spacelift is an infrastructure-as-code orchestration platform that automates plans, applies, policy checks, and drift detection, while recording actions for governance and security. It integrates with Terraform, OpenTofu, Pulumi, CloudFormation, Kubernetes, Ansible, AWS CDK, Serverless, and Terragrunt. Source control connections include Bitbucket, GitHub, GitLab, and Azure DevOps; cloud and notification integrations include AWS, Azure, Google Cloud, Slack, and Microsoft Teams. Governance features include OPA-based policies for plans, approvals, notifications, and security controls, along with Spaces, Contexts, and role-based access control. Deployment options include managed SaaS, self-hosting on a cloud provider, on-premises and air-gapped deployment, and FedRAMP-authorized SaaS. The Free plan costs nothing and includes 2 users and 1 public worker. Starter + costs $20,000 a year as an annual subscription. The pricing FAQ says Starter+, Business, and Enterprise subscriptions are annual and that features or workers cannot be removed from annual subscriptions. Spacelift says customer data is encrypted at rest and in transit and that it holds SOC 2 Type II certification.