Kubernetes

Overview

You can run migetpacks as a Kubernetes Job for one-off or scheduled builds without needing the full Shipwright framework. This approach gives you direct control over the build process while still leveraging Kubernetes for orchestration.

Kubernetes Job

A basic Job that builds and pushes a container image:

apiVersion: batch/v1
kind: Job
metadata:
  name: build-my-app
  namespace: builds
spec:
  backoffLimit: 0  # Don't retry failed builds
  activeDeadlineSeconds: 900  # 15 minute timeout
  template:
    spec:
      restartPolicy: Never
      containers:
        - name: build
          image: miget/migetpacks:latest
          securityContext:
            privileged: true  # Required for Docker-in-Docker
          env:
            - name: OUTPUT_IMAGE
              value: registry.io/your-org/your-app:latest
            - name: LANGUAGE
              value: nodejs
          volumeMounts:
            - name: source
              mountPath: /workspace/source
              readOnly: true
          resources:
            requests:
              cpu: "1"
              memory: "2Gi"
            limits:
              cpu: "4"
              memory: "8Gi"
      volumes:
        - name: source
          persistentVolumeClaim:
            claimName: app-source  # PVC with your source code

The privileged: true security context is required because migetpacks uses Docker-in-Docker (DinD) internally to build images.

Build Cache with PVC

Use a ReadWriteMany (RWX) PersistentVolumeClaim to share package manager caches across builds. This significantly speeds up dependency installation for repeated builds.

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: build-cache
  namespace: builds
spec:
  accessModes:
    - ReadWriteMany  # RWX required for concurrent builds
  resources:
    requests:
      storage: 20Gi
  storageClassName: your-rwx-storage-class  # e.g., nfs, cephfs, efs

Mount it in your Job:

volumeMounts:
  - name: build-cache
    mountPath: /cache
env:
  - name: BUILD_CACHE_DIR
    value: /cache
volumes:
  - name: build-cache
    persistentVolumeClaim:
      claimName: build-cache

The cache stores package manager artifacts per language:

Language	Cache Path	Contents
Node.js	`/cache/npm`, `/cache/yarn`, `/cache/pnpm`	Package tarballs
Python	`/cache/pip`, `/cache/uv`	Wheel files
Ruby	`/cache/bundler`	Gem files
Go	`/cache/go`	Module sources
Rust	`/cache/cargo`	Crate sources
Java	`/cache/maven`, `/cache/gradle`	Dependencies
PHP	`/cache/composer`	Composer packages

ConfigMap for Environment Variables

Use a ConfigMap to manage build configuration separately from the Job definition:

apiVersion: v1
kind: ConfigMap
metadata:
  name: build-config
  namespace: builds
data:
  PORT: "3000"
  USE_DHI: "true"
  REGISTRY_MIRROR: "https://registry.example.io/mirror"
  CACHE_MODE: "max"
  NODE_OPTIONS: "--max-old-space-size=4096"

Reference it in your Job:

containers:
  - name: build
    image: miget/migetpacks:latest
    envFrom:
      - configMapRef:
          name: build-config
    env:
      - name: OUTPUT_IMAGE
        value: registry.io/your-org/your-app:latest

Secret for Registry Credentials

Store registry credentials in a Kubernetes Secret:

apiVersion: v1
kind: Secret
metadata:
  name: registry-credentials
  namespace: builds
type: kubernetes.io/dockerconfigjson
data:
  .dockerconfigjson: <base64-encoded-docker-config>

Mount it as a Docker config file:

containers:
  - name: build
    image: miget/migetpacks:latest
    env:
      - name: DOCKER_CONFIG
        value: /docker-config
    volumeMounts:
      - name: docker-config
        mountPath: /docker-config
volumes:
  - name: docker-config
    secret:
      secretName: registry-credentials
      items:
        - key: .dockerconfigjson
          path: config.json

RESULT_FILE with Shared Volume

Use an emptyDir volume to share build results between the builder and a post-build notification container:

volumes:
  - name: results
    emptyDir: {}

Set the RESULT_FILE environment variable to write results to this volume:

env:
  - name: RESULT_FILE
    value: /workspace/output/build-result.json
volumeMounts:
  - name: results
    mountPath: /workspace/output

The builder always exits with code 0, writing the build status to the result file. Post-build containers should check the status field to determine success or failure.

Post-Build Notification

Use an init container pattern or a sidecar to process build results. Here is an example using a second container that waits for the result file:

containers:
  - name: build
    image: miget/migetpacks:latest
    # ... build configuration ...

  - name: notify
    image: your-rabbitmq-publisher:latest
    command: ["/bin/sh", "-c"]
    args:
      - |
        echo "Waiting for build result..."
        while [ ! -f /workspace/output/build-result.json ]; do
          sleep 2
        done
        echo "Build complete, publishing result..."
        /app/publish-result /workspace/output/build-result.json
    env:
      - name: RABBITMQ_URL
        valueFrom:
          secretKeyRef:
            name: rabbitmq-credentials
            key: url
      - name: RABBITMQ_QUEUE
        value: build-results
    volumeMounts:
      - name: results
        mountPath: /workspace/output

Full Example

A complete Job definition with all components — source, cache, registry credentials, configuration, and post-build notification:

apiVersion: batch/v1
kind: Job
metadata:
  name: build-my-app
  namespace: builds
spec:
  backoffLimit: 0
  activeDeadlineSeconds: 900
  template:
    spec:
      restartPolicy: Never
      containers:
        - name: build
          image: miget/migetpacks:latest
          securityContext:
            privileged: true
          envFrom:
            - configMapRef:
                name: build-config
          env:
            - name: OUTPUT_IMAGE
              value: registry.io/your-org/your-app:latest
            - name: RESULT_FILE
              value: /workspace/output/build-result.json
            - name: BUILD_CACHE_DIR
              value: /cache
            - name: CACHE_IMAGE
              value: registry.io/your-org/your-app:cache
            - name: DOCKER_CONFIG
              value: /docker-config
          volumeMounts:
            - name: source
              mountPath: /workspace/source
              readOnly: true
            - name: build-cache
              mountPath: /cache
            - name: results
              mountPath: /workspace/output
            - name: docker-config
              mountPath: /docker-config
          resources:
            requests:
              cpu: "1"
              memory: "2Gi"
            limits:
              cpu: "4"
              memory: "8Gi"

        - name: notify
          image: your-rabbitmq-publisher:latest
          command: ["/bin/sh", "-c"]
          args:
            - |
              while [ ! -f /workspace/output/build-result.json ]; do sleep 2; done
              /app/publish-result /workspace/output/build-result.json
          env:
            - name: RABBITMQ_URL
              valueFrom:
                secretKeyRef:
                  name: rabbitmq-credentials
                  key: url
          volumeMounts:
            - name: results
              mountPath: /workspace/output

      volumes:
        - name: source
          persistentVolumeClaim:
            claimName: app-source
        - name: build-cache
          persistentVolumeClaim:
            claimName: build-cache
        - name: results
          emptyDir: {}
        - name: docker-config
          secret:
            secretName: registry-credentials
            items:
              - key: .dockerconfigjson
                path: config.json

Getting Started

Guides

Configuration

Languages

Deploying

Reference

Overview

Kubernetes Job

Build Cache with PVC

ConfigMap for Environment Variables

Secret for Registry Credentials

RESULT_FILE with Shared Volume

Post-Build Notification

Full Example

​Overview

​Kubernetes Job

​Build Cache with PVC

​ConfigMap for Environment Variables

​Secret for Registry Credentials

​RESULT_FILE with Shared Volume

​Post-Build Notification

​Full Example

Overview

Kubernetes Job

Build Cache with PVC

ConfigMap for Environment Variables

Secret for Registry Credentials

RESULT_FILE with Shared Volume

Post-Build Notification

Full Example