OpenTofu vs Spacelift

OpenTofu is a free infrastructure as code tool for defining cloud and on-premises resources in human-readable configuration files. Its workflow moves from writing configuration to generating a plan and applying approved changes in dependency order. Providers connect it with cloud platforms, SaaS services and APIs, including AWS, Azure, Google Cloud Platform, Kubernetes, Helm, GitHub, Splunk and Datadog. Reusable modules and a public registry support configurable infrastructure collections. OpenTofu tracks resources in a state file, builds a dependency graph and can change independent resources in parallel. Built-in client-side state encryption supports key providers such as PBKDF2, AWS KMS, GCP KMS and OpenBao. Providers can be installed from registries, local mirrors or caches, including for air-gapped environments. OpenTofu is presented as a Terraform replacement that preserves existing workflows and configurations. OCI registries can host modules and serve as a secondary provider source, but not yet the primary source. Official installation options cover Linux, macOS, Windows, FreeBSD and OCI container images.

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.