kubernetes-sigs/kwok

KWOK is a Kubernetes simulator that enables testing and development by creating thousands of virtual nodes and clusters without running actual Kubelets.

The tool addresses the challenge of testing Kubernetes at scale during development and experimentation. Rather than provisioning real infrastructure, KWOK simulates the Kubernetes control plane's perspective by creating virtual nodes that respond to API requests. This allows developers to test cluster behavior, scheduling decisions, and multi-cluster scenarios without the resource overhead of running full node infrastructure. The simulator works by intercepting Kubernetes API calls and providing realistic responses for simulated nodes and workloads.

KWOK suits teams that need to validate Kubernetes configurations, test scheduling logic, or experiment with multi-cluster setups in resource-constrained environments. It is particularly valuable for continuous integration pipelines, local development workflows, and scenarios where spinning up hundreds or thousands of real nodes would be impractical or expensive. The tool works with standard Kubernetes tooling and integrates with container runtimes including Docker and Nerdctl, making it accessible to developers already familiar with Kubernetes workflows.

The project maintains active development with regular commits addressing bug fixes, feature enhancements, and improvements to simulation fidelity. Pull requests receive timely review and feedback from maintainers. The codebase shows consistent attention to code quality and testing practices. Documentation is actively maintained to reflect current functionality and usage patterns. The project demonstrates responsiveness to user-reported issues and incorporates community contributions into the main branch.