KubeLinter vs Open Policy Agent Gatekeeper
KubeLinter
github.com
Open Policy Agent Gatekeeper
open-policy-agent.github.ioSide by side
| Figure | KubeLinter | Open Policy Agent Gatekeeper |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | Yes |
| macOS | Yes | — |
| Linux | Yes | Yes |
| API | — | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 2 |
| Spec score · Kubernetes Security Software | 7.8 (#14) | 8.3 (#5) |
| Community support | The project invites users to join its Slack workspace to engage with maintainers and other users. | The project site links to a Gatekeeper Slack channel and community meetings. |
| Install options | The project documents installation through Go, release binaries, Homebrew or LinuxBrew, nix-shell, and Docker. | The documentation describes deployment using a prebuilt image, a development image, a locally built image, or Helm. |
| Purpose | KubeLinter statically analyzes Kubernetes YAML files, Helm charts, and Kustomize manifests against best practices for production readiness and security. | Gatekeeper is a validating and mutating Kubernetes webhook that enforces CRD-based policies evaluated by Open Policy Agent. |
| Vulnerability reporting | The security policy directs confidential vulnerability reports to Red Hat's Product Security team. | The project asks vulnerability reporters to email its security group and says it will acknowledge reports and follow up after investigation. |
Plans
Open Policy Agent Gatekeeper
- GatekeeperFree
- Open-source GatekeeperFree
In their own words
KubeLinter
KubeLinter is a free, open-source static analyzer for Kubernetes YAML files, Helm charts, and Kustomize manifests. It checks production-readiness and security practices, including non-root containers, least privilege, and keeping sensitive information in secrets. Users can enable or disable checks and create custom checks for organizational policies. Failed checks produce remediation recommendations and a non-zero exit code. KubeLinter can generate several output formats in one run, including SARIF and JSON, and supports pull request scanning. Documented installation methods include Go, release binaries, Homebrew or LinuxBrew, nix-shell, and Docker. Container images are signed with cosign, with a public verification key supplied. The project uses the Apache License 2.0 and lists no paid tiers. Its README identifies StackRox as creator and Red Hat as current maintainer. The README also warns that commands, flags, and configuration formats may change. The latest listed release is v0.8.3.
Open Policy Agent Gatekeeper
Open Policy Agent Gatekeeper is a free, open-source Kubernetes policy controller for Linux and self-hosted deployments. It runs as a validating and mutating webhook, enforcing CRD-based policies evaluated by Open Policy Agent. Validation constraints can deny requests, warn, run in dry-run mode or report violations without changing resources. Mutation policies can alter matching resources during admission before validation checks the final object. An audit function periodically evaluates existing cluster resources against constraints to identify pre-existing misconfigurations. The project includes an extensible policy library with parameterized examples, and provider connections to external data such as image registries and directory services. Named integrations or backed services include Azure Policy for Kubernetes, Google Kubernetes Engine Policy Controller, Rancher, AWS EKS Blueprints and Alibaba Cloud. Installation options include prebuilt, development or locally built images and Helm. Gatekeeper requires Kubernetes resources introduced in version 1.16 and cluster-admin permissions for installation. The gator CLI is documented as beta from version 3.11.