Zero code changes required - Annotate a Service and zen-lead creates leader Service + EndpointSlice
zen-lead is a non-invasive leader election controller for Kubernetes that provides network-level single-active routing without requiring application code changes or mutating workload pods.
Key Differentiation: Unlike client-go leader election libraries (which require application code changes), zen-lead provides a network contract that works for any client, any language, without code changes. Simply annotate a Service and connect to the leader Service endpoint.
Applications don't need to know about leader election - just connect to the leader Service
No pod mutation, no changes to user resources - only creates leader Service and EndpointSlice
Controller-driven leader selection based on pod readiness with fast failover (1.0-1.3s average)
Secure defaults, namespace-scoped, event-driven reconciliation, HA controller with leader election
Prometheus metrics, Grafana dashboards, and alert rules for full visibility
Uses standard Kubernetes primitives - no CRDs, no webhooks, no pod mutation
kubectl annotate service my-app zen-lead.io/enabled=true
Automatically creates my-app-leader Service (selector-less) and EndpointSlice pointing to leader pod
# Update your application config env: - name: SERVICE_NAME value: my-app-leader # Points only to current leader
zen-lead is coming soon! Check out the repository and feel free to contribute.