# ADR-0001: Seedling Template Design Philosophy

> "Design is not just what it looks like and feels like. Design is how it works."
> — **Steve Jobs**

## Status
Accepted

## Context
We need a world-class Python project template that provides:
- Modern development workflow with best practices
- Comprehensive CI/CD pipeline
- Excellent developer experience
- AI agent compatibility
- Enterprise-grade quality standards
- Reproducible project generation

## Decision
Build the seedling template using **Copier + uv + Nox + Just + Sphinx + pre-commit-ci** as the core technology stack.

## Consequences

### Positive Consequences

#### **Copier (Template Engine)**
- **Jinja2 templating**: More powerful than Cookiecutter's limited templating
- **Better dependency management**: Handles template updates and dependencies
- **Modern Python support**: Built with modern Python practices
- **Version control integration**: Better git integration and update handling
- **Conditional templating**: Advanced logic for conditional file generation

#### **uv (Package Manager)**
- **10-100x faster than pip**: Dramatically improved installation speed
- **Lockfile advantages**: Reproducible builds with uv.lock
- **Modern Python tooling**: Built for modern Python development
- **Modern Python tooling**: Built for modern Python development
- **Cross-platform**: Works consistently across all platforms

#### **Nox (Build System)**
- **Multi-environment testing**: Test against multiple Python versions
- **Session management**: Clean separation of different tasks
- **CI integration**: Perfect integration with GitHub Actions
- **Extensible**: Easy to add new sessions and tasks
- **Python-native**: Built specifically for Python projects

#### **Just (Task Runner)**
- **Cross-platform compatibility**: Works on Windows, macOS, and Linux
- **Dependency management**: Handles task dependencies automatically
- **Readability**: Simple, readable syntax
- **No dependencies**: Single binary, no Python installation required
- **IDE integration**: Works well with modern IDEs

#### **Sphinx (Documentation)**
- **Documentation standards**: Industry standard for Python documentation
- **Extensibility**: Rich ecosystem of extensions
- **Hosting integration**: Perfect for GitHub Pages deployment
- **Search functionality**: Built-in search capabilities
- **Versioning**: Support for multiple documentation versions

#### **pre-commit-ci (Quality Assurance)**
- **Automated quality enforcement**: Runs quality checks on every PR
- **Team collaboration**: Ensures consistent code quality across team
- **Auto-fix capabilities**: Automatically fixes formatting issues
- **GitHub integration**: Seamless integration with GitHub workflows
- **Configurable**: Flexible configuration for different project needs

### Negative Consequences

#### **Learning Curve**
- **New tools**: Team members need to learn uv, Nox, and Just
- **Template complexity**: More complex than simple cookiecutter templates
- **Configuration overhead**: More configuration files to maintain

#### **Dependencies**
- **Tool requirements**: Requires specific versions of tools
- **Platform considerations**: Some tools may have platform-specific issues
- **Update management**: Need to keep template and tools in sync

#### **Maintenance**
- **Template maintenance**: More complex template to maintain
- **Documentation**: Need to document template usage and customization
- **Testing**: More complex testing requirements for template

## Implementation Details

### Template Structure
```
seedling/
├── copier.yml              # Template configuration
├── seedling/               # Template files
│   ├── src/{{ project_slug }}/
│   ├── tests/
│   ├── docs/
│   ├── .github/workflows/
│   └── *.jinja files
└── docs/                   # Template documentation
    └── adr/               # Architecture Decision Records
```

### Key Design Principles
1. **Modularity**: Each tool has a specific, well-defined role
2. **Extensibility**: Easy to add new features and customizations
3. **Consistency**: Consistent patterns across all generated projects
4. **Quality**: Built-in quality gates and best practices
5. **Modern**: Uses latest Python development practices

### Quality Standards
- **Type Safety**: Full MyPy integration with strict mode
- **Code Quality**: Ruff linting with comprehensive rules
- **Test Coverage**: Minimum 80% coverage requirement
- **Documentation**: Comprehensive docstrings and examples
- **Security**: Regular dependency vulnerability scanning

## Related ADRs
- [ADR-0002: Technology Stack Rationale](./0002-technology-stack.md)
- [ADR-0003: Architecture Decisions](./0003-architecture-decisions.md)

## References
- [Copier Documentation](https://copier.readthedocs.io/)
- [uv Documentation](https://docs.astral.sh/uv/)
- [Nox Documentation](https://nox.thea.codes/)
- [Just Documentation](https://just.systems/)
- [Sphinx Documentation](https://www.sphinx-doc.org/)
- [pre-commit-ci Documentation](https://pre-commit.ci/)