PHP

Detection

migetpacks detects a PHP application when any of the following files are present in the project root:

composer.json
index.php

Version Detection

PHP version is resolved in the following priority order:

Source	Example
`.php-version`	`8.3`
`composer.json` (`require.php`)	`"php": ">=8.2"`
Default	`8.3`

Version constraints from composer.json (e.g., >=8.2, ^8.3) are normalized to Docker-compatible versions.

FrankenPHP supports PHP 8.2, 8.3, and 8.4. Older versions will fall back to PHP 8.2 with a warning.

Build Process

migetpacks generates a multi-stage Dockerfile using FrankenPHP (a modern PHP application server built on Go and Caddy):

# Build stage
FROM dunglas/frankenphp:builder-php8.3 AS builder
WORKDIR /build

# Install PHP extensions detected from composer.json
RUN apt-get update && apt-get install -y ... \
    && docker-php-ext-install pdo_pgsql gd ...

# Layer caching: copy dependency files first
COPY composer.json composer.lock* ./

# Install Composer and dependencies (cached if lockfiles unchanged)
RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer \
    && composer install --no-dev --optimize-autoloader --no-scripts

# Copy source code
COPY . .

# Runtime stage
FROM dunglas/frankenphp:php8.3
WORKDIR /app
COPY --from=builder --chown=1000:1000 /build /app

PHP Extension Detection

Extensions declared in composer.json under require with the ext- prefix are automatically installed:

{
  "require": {
    "ext-pdo_pgsql": "*",
    "ext-gd": "*",
    "ext-intl": "*"
  }
}

Web Root Detection

migetpacks automatically detects the web root directory by checking for these directories (in order):

web/
public/
html/
www/
. (project root, fallback)

Run Command

The default run command uses FrankenPHP with Caddy:

frankenphp run --config /etc/caddy/Caddyfile

Override with RUN_COMMAND or a Procfile:

web: frankenphp run --config /etc/caddy/Caddyfile

PHP Configuration

Production PHP settings are automatically configured via environment variables:

Setting	Default
`memory_limit`	`256M`
`max_execution_time`	`30`
`upload_max_filesize`	`32M`
`opcache.enable`	`1`
`display_errors`	`Off`
`session.cookie_secure`	`1`

These can be overridden at runtime by setting the corresponding PHP_INI_* environment variable (e.g., PHP_INI_MEMORY_LIMIT=512M).

Caching

Layer Caching

Dependencies are cached by copying composer.json and composer.lock before the full source:

Scenario	Dependency Install
First build	Runs
Source code change only	Cached
Lockfile change	Runs

BUILD_CACHE_DIR

When BUILD_CACHE_DIR is set, Composer packages are cached at:

Cache Path	Contents
`/cache/composer`	Composer package cache

DHI Support

Docker Hardened Images (DHI) are not supported for PHP. FrankenPHP is a specialized application server that requires its own base image.

When USE_DHI=true is set, migetpacks will continue to use the standard FrankenPHP images.

Example

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

With custom environment variables

docker run --rm \
  -v /path/to/php-app:/workspace/source \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e OUTPUT_IMAGE=my-php-app:latest \
  -e PHP_INI_MEMORY_LIMIT=512M \
  -e APP_ENV=production \
  miget/migetpacks:latest

Getting Started

Guides

Configuration

Languages

Deploying

Reference

Detection

Version Detection

Build Process

PHP Extension Detection

Web Root Detection

Run Command

PHP Configuration

Caching

Layer Caching

BUILD_CACHE_DIR

DHI Support

Example

With custom environment variables

​Detection

​Version Detection

​Build Process

​PHP Extension Detection

​Web Root Detection

​Run Command

​PHP Configuration

​Caching

​Layer Caching

​BUILD_CACHE_DIR

​DHI Support

​Example

​With custom environment variables

Detection

Version Detection

Build Process

PHP Extension Detection

Web Root Detection

Run Command

PHP Configuration

Caching

Layer Caching

BUILD_CACHE_DIR

DHI Support

Example

With custom environment variables