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Overview

migetpacks integrates with GitHub Actions to build and push container images as part of your CI/CD pipeline. It works with both self-hosted runners (recommended for performance) and GitHub-hosted runners.

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Self-Hosted Runner

Self-hosted runners offer the best performance because Docker layer caches and package manager caches persist between builds. 
name: Build with migetpacks

on:
  push:
    branches: [main]

jobs:
  build:
    runs-on: self-hosted

    steps:
      - uses: actions/checkout@v4

      - name: Log into registry
        uses: docker/login-action@v3
        with:
          registry: your-registry.io
          username: ${{ secrets.REGISTRY_USERNAME }}
          password: ${{ secrets.REGISTRY_PASSWORD }}

      - name: Setup cache directory
        run: mkdir -p /home/runner/migetpacks-cache

      - name: Build with migetpacks
        run: |
          docker run --rm \
            -v ${{ github.workspace }}:/workspace/source:ro \
            -v /var/run/docker.sock:/var/run/docker.sock \
            -v /home/runner/migetpacks-cache:/cache \
            -e OUTPUT_IMAGE=your-registry.io/app:${{ github.sha }} \
            -e BUILD_CACHE_DIR=/cache \
            -e REGISTRY_MIRROR=https://registry.example.io/mirror \
            -e USE_DHI=true \
            miget/migetpacks:latest
The persistent cache directory (/home/runner/migetpacks-cache) survives runner restarts and dramatically speeds up dependency installation on subsequent builds.

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GitHub-Hosted Runner

GitHub-hosted runners do not persist Docker layer caches between runs. Use CACHE_IMAGE for registry-based caching to speed up builds. 
name: Build with migetpacks

on:
  push:
    branches: [main]
  pull_request:

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4

      - name: Log into registry
        uses: docker/login-action@v3
        with:
          registry: your-registry.io
          username: ${{ secrets.REGISTRY_USERNAME }}
          password: ${{ secrets.REGISTRY_PASSWORD }}

      - name: Build with migetpacks
        run: |
          docker run --rm \
            -v ${{ github.workspace }}:/workspace/source:ro \
            -v /var/run/docker.sock:/var/run/docker.sock \
            -e OUTPUT_IMAGE=your-registry.io/app:${{ github.sha }} \
            -e CACHE_IMAGE=your-registry.io/app:buildcache \
            -e CACHE_MODE=max \
            miget/migetpacks:latest

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Configuration Options

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Registry Login

Always authenticate before running migetpacks if you are pushing to a private registry: 
- name: Log into Docker Hub
  uses: docker/login-action@v3
  with:
    username: ${{ secrets.DOCKERHUB_USERNAME }}
    password: ${{ secrets.DOCKERHUB_TOKEN }}

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Build Cache Directory

BUILD_CACHE_DIR enables shared package manager caching. On self-hosted runners, point this to a persistent directory: 
- name: Setup cache directory
  run: mkdir -p /home/runner/migetpacks-cache

- name: Build with migetpacks
  run: |
    docker run --rm \
      -v /home/runner/migetpacks-cache:/cache \
      -e BUILD_CACHE_DIR=/cache \
      ...

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Registry Mirror

REGISTRY_MIRROR configures a pull-through cache for Docker Hub images, reducing image pull times: 
-e REGISTRY_MIRROR=https://your-mirror.example.com

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Custom Environment Variables

Pass build-time environment variables directly: 
- name: Build with migetpacks
  run: |
    docker run --rm \
      -v ${{ github.workspace }}:/workspace/source:ro \
      -v /var/run/docker.sock:/var/run/docker.sock \
      -e OUTPUT_IMAGE=your-registry.io/app:${{ github.sha }} \
      -e NODE_OPTIONS="--max-old-space-size=4096" \
      -e NEXT_PUBLIC_API_URL="${{ vars.API_URL }}" \
      -e RAILS_MASTER_KEY="${{ secrets.RAILS_MASTER_KEY }}" \
      miget/migetpacks:latest
Secrets like RAILS_MASTER_KEY are injected as build-time environment variables and will be present in the generated Dockerfile. They are visible in the final image’s environment. Use runtime secrets injection for sensitive values in production.

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Full Workflow Example

This complete workflow builds on push to main, tags with both commit SHA and latest, and uses all available caching strategies: 
name: Build and Push

on:
  push:
    branches: [main]

jobs:
  build:
    runs-on: self-hosted

    steps:
      - uses: actions/checkout@v4

      - name: Log into registry
        uses: docker/login-action@v3
        with:
          registry: your-registry.io
          username: ${{ secrets.REGISTRY_USERNAME }}
          password: ${{ secrets.REGISTRY_PASSWORD }}

      - name: Setup persistent cache
        run: mkdir -p /home/runner/migetpacks-cache

      - name: Build with migetpacks
        run: |
          docker run --rm \
            -v ${{ github.workspace }}:/workspace/source:ro \
            -v /var/run/docker.sock:/var/run/docker.sock \
            -v /home/runner/migetpacks-cache:/cache \
            -e OUTPUT_IMAGE=your-registry.io/app:${{ github.sha }} \
            -e BUILD_CACHE_DIR=/cache \
            -e CACHE_IMAGE=your-registry.io/app:buildcache \
            -e CACHE_MODE=max \
            -e REGISTRY_MIRROR=https://registry.example.io/mirror \
            -e USE_DHI=true \
            miget/migetpacks:latest

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Performance Tips

  • Persistent cache: Use BUILD_CACHE_DIR pointed at a local directory
  • Pre-pull images: Pull common base images during runner initialization
  • Registry mirror: Use REGISTRY_MIRROR for Docker Hub images
  • Local Docker cache: Docker layer cache persists in /var/lib/docker
  • NVMe storage: Use local SSD/NVMe for /var/lib/docker instead of network storage