Knative 0.1: Google’s Serverless Building Blocks for Kubernetes

Introduction

At Google Cloud Next ’18 on July 24, 2018, Google, Pivotal, and IBM unveiled Knative 0.1—a collection of open-source building blocks that bring serverless workflows directly onto Kubernetes. Knative bundles three core components: Serving, Build, and Eventing, each designed to be pluggable with your favorite mesh, CI, and messaging stacks.

Knative Components

Serving

• Deploys containerized workloads with URL routing, autoscaling to zero, and revision management.
• Integrates tightly with Istio/Envoy for traffic splitting and mTLS.
• Offers declarative Service specs that abstract away Deployment/Service boilerplate.

Build (now Tekton Pipelines)

• Transforms source to container images using container-based build steps.
• Supports Kaniko, Buildpacks, and Dockerfile builds out of the box.
• Pipeline CRDs orchestrate multi-step builds on Kubernetes.

Eventing

• Unifies event sources (GitHub, Pub/Sub, Kafka) with channel/broker abstractions.
• Uses CloudEvents to model payloads for cross-platform portability.
• Connects seamlessly to Serving endpoints for function-style consumers.

Getting Started

1. Install Istio 1.0 with mutual TLS enabled.

2. Apply Knative CRDs and controllers (kubectl apply -f knative/docs/.../serving.yaml).

3. Deploy your first service:

   apiVersion: serving.knative.dev/v1alpha1
   kind: Service
   metadata:
     name: hello
   spec:
     template:
       spec:
         containers:
         - image: gcr.io/knative-samples/helloworld-go
           env:
           - name: TARGET
             value: "KubeCon"
   

4. Use knative/build to transform Git repos into OCI images, then hook Eventing to trigger redeployments.

Ecosystem Fit

• Works alongside Prometheus 2.3 via built-in autoscaler metrics.
• Consumes Envoy 1.7 features for smarter traffic management.
• Pairs with gVisor to sandbox user-provided serverless functions.

Roadmap & Limitations

• Expect rapid API changes while the project stabilizes; CRDs are still v1alpha1.
• Build component will evolve into Tekton Pipelines for richer CI/CD.
• Eventing sources are limited—Kafka, GitHub, and Cron, with more promised.

Reality checks before you pitch it internally

• Cold starts are part of the deal: autoscale-to-zero is great for cost and spiky traffic, but it introduces latency on the first request.
• It’s an integration project: Serving, Build, and Eventing each pull in dependencies (ingress/mesh, image building, brokers). Plan for the operational surface area.
• Treat 0.1 as exploratory: use it for prototypes and platform learning, not as a drop-in replacement for a mature PaaS.

Summary

Knative’s first release gave platform teams a blueprint for cloud-native serverless on their own clusters. Even in alpha, it signaled a future where Kubernetes hosts both microservices and event-driven workloads with the same operational toolkit.