migetpacks

Auto-detecting buildpacks for container images - automatically detects your language, version, and builds optimized container images using official upstream Docker images.

Built by miget.com - Unlimited apps, one price.

Features

Zero Config - Automatically detects language, version, and builds your app
14 Languages - Node.js, Deno, Bun, Python, Ruby, Go, Rust, Java, Kotlin, Scala, Clojure, .NET, PHP, Elixir
Secure by Default - Optional Docker Hardened Images (distroless, CVE-free)
Multi-Buildpack - Combine languages (e.g., Ruby + Node.js for asset compilation)
Procfile Support - Standard process definitions
Non-root Runtime - All containers run as non-root user
Fast Builds - BuildKit layer caching and registry-based caching

Requirements

Docker Desktop (macOS/Windows) or Docker Engine (Linux)
BuildKit enabled (default in Docker Desktop 4.0+)

migetpacks runs Docker-in-Docker using BuildKit for optimized multi-stage builds. It requires access to the Docker socket (/var/run/docker.sock).

# Verify Docker is running
docker info

# Verify BuildKit is available
docker buildx version

Quick Start

Docker

# Build your app
docker run --rm \
  -v /path/to/your/app:/workspace/source \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e OUTPUT_IMAGE=my-app:latest \
  miget/migetpacks:latest

# Run your app
docker run -p 5000:5000 my-app:latest

GitHub Actions (GitHub-hosted runners)

For ephemeral ubuntu-latest runners, use registry-based caching via CACHE_IMAGE:

name: Build and Push

on:
  push:
    branches: [main]

jobs:
  build:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write

    steps:
      - uses: actions/checkout@v4

      - name: Log in to GitHub Container Registry
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      # Required for CACHE_IMAGE support
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Build and push with migetpacks
        run: |
          docker run --rm \
            -v ${{ github.workspace }}:/workspace/source:ro \
            -v /var/run/docker.sock:/var/run/docker.sock \
            -v /home/runner/.docker/config.json:/root/.docker/config.json:ro \
            -e OUTPUT_IMAGE=ghcr.io/${{ github.repository }}:${{ github.sha }} \
            -e CACHE_IMAGE=ghcr.io/${{ github.repository }}:cache \
            miget/migetpacks:latest

GitHub Actions (Self-hosted runners)

For persistent self-hosted runners, use local file cache via BUILD_CACHE_DIR:

name: Build and Push

on:
  push:
    branches: [main]

jobs:
  build:
    runs-on: self-hosted

    steps:
      - uses: actions/checkout@v4

      - name: Log in to registry
        uses: docker/login-action@v3
        with:
          registry: registry.example.com
          username: ${{ secrets.REGISTRY_USERNAME }}
          password: ${{ secrets.REGISTRY_PASSWORD }}

      - name: Build and push with migetpacks
        run: |
          docker run --rm \
            -v ${{ github.workspace }}:/workspace/source:ro \
            -v /var/run/docker.sock:/var/run/docker.sock \
            -v $HOME/.docker/config.json:/root/.docker/config.json:ro \
            -v /var/cache/migetpacks:/cache \
            -e OUTPUT_IMAGE=registry.example.com/my-app:${{ github.sha }} \
            -e BUILD_CACHE_DIR=/cache \
            miget/migetpacks:latest

Cache options:

CACHE_IMAGE - Registry-based BuildKit layer cache. Requires docker/setup-buildx-action. Works on ephemeral runners.
BUILD_CACHE_DIR - Local directory for package manager caches (npm, pip, bundler, etc.). Best for persistent self-hosted runners.

Supported Languages

| Language | Detection | Version Source | |----------|-----------|----------------| | Node.js | package.json | .nvmrc, .node-version, package.json | | Deno | deno.json, deno.jsonc | deno.json | | Bun | bun.lockb, bunfig.toml | package.json | | Python | requirements.txt, Pipfile, pyproject.toml | .python-version, runtime.txt | | Ruby | Gemfile | .ruby-version, Gemfile | | Go | go.mod | go.mod | | Rust | Cargo.toml | Cargo.toml | | PHP | composer.json, index.php | composer.json | | Java | pom.xml, build.gradle | pom.xml, .java-version, system.properties | | Kotlin | build.gradle.kts | system.properties | | Scala | build.sbt | system.properties | | Clojure | project.clj, deps.edn | system.properties | | .NET | *.csproj, *.fsproj | global.json, *.csproj | | Elixir | mix.exs | mix.exs, .elixir-version | | Dockerfile | Dockerfile | - | | Compose | compose.yaml, docker-compose.yml | - |

Environment Variables

| Variable | Required | Default | Description | |----------|----------|---------|-------------| | OUTPUT_IMAGE | Yes | - | Target image name (e.g., ghcr.io/user/app:tag) | | SOURCE_DIR | No | /workspace/source | Source code directory | | LANGUAGE | No | auto-detected | Force language (see values below) | | RUN_COMMAND | No | from Procfile | Override the run command | | PORT | No | 5000 | Application port | | ARCH | No | x86_64 | Target architecture (x86_64, arm64) | | PROJECT_PATH | No | - | Subdirectory for monorepo builds | | BUILDPACKS | No | auto-detected | Explicit buildpack order (e.g., ruby,nodejs) | | DOCKERFILE_PATH | No | - | Custom Dockerfile path (forces dockerfile language) | | COMPOSE_FILE | No | - | Custom compose file path (forces compose language) | | TAG_LATEST | No | false | Also tag image with :latest in addition to primary tag | | RESULT_FILE | No | - | Path to write build results JSON | | STORAGE_DRIVER | No | overlay2 | Docker storage driver (e.g., fuse-overlayfs for nested DinD) |

Caching Options

| Variable | Required | Default | Description | |----------|----------|---------|-------------| | CACHE_IMAGE | No | - | Registry image for BuildKit cache | | CACHE_MODE | No | min | BuildKit cache export mode: min (final layer) or max (all layers) | | CACHE_FROM | No | - | Additional read-only cache sources (comma-separated registry refs) | | CACHE_REGISTRY_INSECURE | No | false | Set to true for HTTP registries | | NO_CACHE | No | false | Force fresh build, skips cache-from | | BUILD_CACHE_DIR | No | - | Directory for package manager cache | | REGISTRY_MIRROR | No | - | Docker registry mirror URL |

Docker Hardened Images

| Variable | Required | Default | Description | |----------|----------|---------|-------------| | USE_DHI | No | false | Use Docker Hardened Images from dhi.io | | DHI_USERNAME | No | - | DHI registry username (alternative to mounting docker config) | | DHI_PASSWORD | No | - | DHI registry password/token | | DHI_MIRROR | No | - | DHI registry mirror URL |

Custom Build Environment Variables

Any environment variable passed to migetpacks that is not a known configuration variable will be automatically injected into the generated Dockerfile as ENV statements. This allows you to pass custom build-time settings without modifying migetpacks.

# Pass NODE_OPTIONS to increase heap size for large builds
docker run --rm \
  -v ./my-app:/workspace/source \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e OUTPUT_IMAGE=my-app:latest \
  -e NODE_OPTIONS="--max-old-space-size=4096" \
  miget/migetpacks:latest

# Pass multiple custom variables
docker run --rm \
  -v ./my-app:/workspace/source \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e OUTPUT_IMAGE=my-app:latest \
  -e NODE_OPTIONS="--max-old-space-size=4096" \
  -e VITE_API_URL="https://api.example.com" \
  -e MY_BUILD_FLAG="true" \
  miget/migetpacks:latest

Common use cases:

NODE_OPTIONS="--max-old-space-size=4096" - Increase Node.js heap for large builds
VITE_* / NEXT_PUBLIC_* - Frontend build-time variables
RAILS_MASTER_KEY - Rails credentials key for asset precompilation
Custom feature flags for conditional compilation

Note: Sensitive variables like AWS_* credentials and Docker configuration are automatically filtered out and never injected into the Dockerfile.

LANGUAGE Values

Force a specific language by setting LANGUAGE:

| Value | Description | |-------|-------------| | nodejs | Node.js (npm, yarn, pnpm) | | deno | Deno runtime | | bun | Bun runtime | | python | Python (pip, uv) | | ruby | Ruby (bundler) | | go | Go | | rust | Rust (cargo) | | php | PHP (FrankenPHP + Composer) | | java | Java (Maven or Gradle) | | kotlin | Kotlin (Gradle) | | scala | Scala (sbt) | | clojure | Clojure (Leiningen) | | .net or dotnet | .NET / C# | | elixir | Elixir (Mix) | | dockerfile | Use project's Dockerfile directly | | compose | Build all services from compose.yaml |

Procfile Support

Define processes in a Procfile:

web: bundle exec puma -C config/puma.rb
worker: bundle exec sidekiq
release: bundle exec rails db:migrate

Priority order:

RUN_COMMAND environment variable
web: process from Procfile
First process in Procfile
Language-specific default

Multi-Buildpack

Build apps with multiple languages:

# Ruby app with Node.js for asset compilation
docker run --rm \
  -v ./my-rails-app:/workspace/source \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e OUTPUT_IMAGE=my-rails-app:latest \
  -e BUILDPACKS=ruby,nodejs \
  miget/migetpacks:latest

Migetpacks

Install / Use

README