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Alex Spinov
Alex Spinov

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Knative Has a Free API: Serverless Containers on Kubernetes Without the Complexity

#kubernetes #serverless #cloudnative #devops

Why Knative Matters

Knative brings serverless capabilities to Kubernetes. Deploy containers that automatically scale to zero when idle and scale up instantly on demand — no Lambda-style vendor lock-in.

Install Knative Serving 

kubectl apply -f https://github.com/knative/serving/releases/latest/download/serving-crds.yaml
kubectl apply -f https://github.com/knative/serving/releases/latest/download/serving-core.yaml
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Deploy a Serverless Service 

apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  name: hello-world
spec:
  template:
    spec:
      containers:
        - image: ghcr.io/knative/helloworld-go:latest
          ports:
            - containerPort: 8080
          env:
            - name: TARGET
              value: "World"
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kubectl apply -f service.yaml
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Key Features

  • Scale to zero — pods terminate when no traffic, saving resources
  • Auto-scaling — handles traffic spikes automatically with KPA or HPA
  • Traffic splitting — canary deployments with percentage-based routing
  • Revisions — every deployment creates an immutable revision
  • Custom domains — map your own domains to services

Traffic Splitting for Canary Deploys 

apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  name: hello-world
spec:
  template:
    metadata:
      name: hello-world-v2
    spec:
      containers:
        - image: ghcr.io/knative/helloworld-go:latest
  traffic:
    - revisionName: hello-world-v1
      percent: 80
    - revisionName: hello-world-v2
      percent: 20
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Knative Eventing

Knative Eventing enables event-driven architectures:

apiVersion: sources.knative.dev/v1
kind: ApiServerSource
metadata:
  name: k8s-events
spec:
  serviceAccountName: events-sa
  mode: Resource
  resources:
    - apiVersion: v1
      kind: Event
  sink:
    ref:
      apiVersion: serving.knative.dev/v1
      kind: Service
      name: event-display
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Knative vs Traditional K8s Deployments

Feature K8s Deployment Knative Service
Scale to zero No Yes
Auto-scaling HPA only Built-in KPA
Traffic split Ingress rules Native support
Revisions Manual Automatic
Cold start N/A ~1-3 seconds

Resources

Need to scrape Kubernetes configs, cloud APIs, or infrastructure data at scale? Check out my data extraction tools on Apify or email spinov001@gmail.com for custom scraping solutions.

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