.cline-rules

# Cline Rules for docker-php-alpine Repository

## Repository Overview

docker-php-alpine provides Docker images for PHP applications running on Alpine Linux.

## Code Standards and Practices

### Docker Standards

- Follow Docker best practices for image optimization
- Use appropriate base images and multi-stage builds
- Implement security hardening practices
- Document exposed ports and volumes clearly

### Documentation Standards

- Include clear Docker usage examples and docker-compose files
- Document PHP version compatibility and extensions
- Provide build and deployment instructions
- Use markdown formatting consistently

### Markdown Compliance Requirements

- **ALL markdown files (.md) MUST pass markdownlint validation with zero errors or warnings**
- Run `markdownlint <filename>` on every markdown file before considering it complete
- Follow the project's `.markdownlint.json` configuration strictly
- Address ALL markdownlint issues immediately - no exceptions or workarounds
- Common requirements include:
  - Maximum line length of 80 characters (MD013)
  - Consistent heading styles and hierarchy
  - Proper list formatting and indentation
  - Blank lines around headings and code blocks
  - Consistent link and reference formatting
  - No trailing whitespace
  - Files must end with newlines
  - Proper table formatting when applicable
- Use `markdownlint --fix <filename>` for auto-fixable issues when available
- Validate markdown files in CI/CD pipelines where applicable

## Development Guidelines

### When Making Changes

- Preserve existing functionality unless explicitly asked to change it
- Update documentation when changing PHP versions or extensions
- **Always run markdownlint and fix all issues in markdown files before considering changes complete**

### Container Standards

- Keep images minimal and secure using Alpine Linux
- Test images across different architectures
- Implement proper user permissions and security contexts
- Provide clear upgrade paths for new PHP versions