Gardener is an open source system that delivers Kubernetes clusters as a service across infrastructures: an extension API server and controllers that host cluster control planes (“shoots”) inside “seed” clusters, with a validated extensibility framework for any cloud or infrastructure provider. It is software, not a specification; its standards contribution is the *.gardener.cloud Kubernetes API it defines. Apache 2.0, since 2018.
Gardener
Gardener manages Kubernetes clusters with Kubernetes: clusters are declared as resources and reconciled by controllers, and control planes run as workloads in other clusters. It is part of NeoNephos, a Linux Foundation Europe project.
- An API, not just a tool - Aggregated and custom resource APIs under
pkg/apis/— core, extensions, operations, operator, resources, security, seedmanagement — in the*.gardener.cloudgroups. - Provider extensibility - Infrastructure, operating system and DNS providers plug in through extension resources, OpenStack among them.
- Certified - Listed as CNCF Certified Kubernetes up to v1.35.
- Mature and busy - Created in 2018; v1.153.0 released 8 October 2026.
