Phoenix Expert

---
name: phoenix-expert
description: Use when implementing phoenix functionality with production-grade patterns and safeguards.
metadata:
  hermes:
    tags: [codex-agent, general]
    source: codex-field-kit/general
---

# Phoenix Expert

## Focus Areas

- Mastery of Phoenix framework components like channels, routers, and controllers
- Building scalable real-time applications using Phoenix Channels and Presence
- Understanding Ecto and database interactions within Phoenix
- Efficient handling of request/response cycle in Phoenix applications
- Proper use of templates and views in Phoenix for dynamic content rendering
- Establishing secure authentication with Phoenix applications using Plug
- Effective error management and logging strategies within Phoenix
- Optimization of HTTP and WebSocket performance in Phoenix apps
- Understanding Phoenix Contexts for modular application design
- Implementation of testing strategies tailored for Phoenix applications

## Approach

- Follow Phoenix conventions for folder structure and application flow
- Prioritize real-time features, ensuring low-latency interactions
- Utilize Elixir's concurrency model to handle I/O bound operations efficiently
- Leverage the power of LiveView for interactive, real-time UI updates
- Integrate Phoenix with Postgres using Ecto for a smooth data layer
- Implement comprehensive tests using ExUnit for all Phoenix components
- Focus on secure configurations and protect against common web vulnerabilities
- Use code formatting tools like mix format to maintain code consistency
- Keep dependencies updated and manage with Mix while ensuring compatibility
- Encourage contributions and support via Phoenix/Elixir community guidelines

## Quality Checklist

- Adherence to Phoenix and Elixir coding standards and best practices
- Comprehensive and understandable documentation for each Phoenix component
- Achieve high test coverage with meaningful test cases, including edge scenarios
- Maintain backwards compatibility and plan for future Phoenix upgrades
- Monitor application performance and use benchmarks to guide optimization
- Ensure responsive, seamless user experiences across various devices and browsers
- Proper implementation and documentation of RESTful APIs using Phoenix
- Utilize Phoenix's built-in generators for rapid and consistent development
- Implement fallbacks for error pages and articulate error-handling strategies
- Follow industry standards for user authentication, data validation, and encryption

## Output

- Phoenix web applications using channels and contexts for modular and scalable architecture
- Real-time features correctly implemented using Phoenix LiveView and Channels
- Well-defined APIs and standardized HTTP responses through Phoenix controllers
- Robust integration of database schemas and queries via Ecto framework
- Secure, maintainable applications with a focus on user privacy and data protection
- Thoroughly tested components with clear documentation and minimal tech debt
- Optimized server-side rendering and efficient client-server communication
- Pluggable architecture for authentication and authorization systems
- Straightforward deployment procedures and CI/CD pipeline recommendations
- Engage with the Phoenix community for continual learning and collaboration opportunities