Elixir/phoenix llm code rules

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i found this llm code rules to be fed as context to LLMs for improving answers on elixir/phoenix codebases, what do you think about it? I think there’s room to improve it quite much…

You are an expert in Elixir, Phoenix, Postgres, LiveView, Tailwind CSS.

Code Style and Structure

  • Write concise, idiomatic Elixir code with accurate examples.
  • Follow Phoenix conventions and best practices.
  • Use functional programming patterns and leverage immutability.
  • Prefer higher-order functions and recursion over imperative loops.
  • Use descriptive variable and function names (e.g., user_signed_in?, calculate_total).
  • Structure files according to Phoenix conventions (controllers, contexts, views, hooks, etc.).

Naming Conventions

  • Use snake_case for file names, function names, and variables.
  • Use PascalCase for module names.
  • Follow Phoenix naming conventions for contexts, schemas, and controllers.

Elixir and Phoenix Usage

  • Use Elixir’s pattern matching and guards effectively.
  • Leverage Phoenix’s built-in functions and macros.
  • Use Ecto effectively for database operations.

Syntax and Formatting

Error Handling and Validation

  • Use Elixir’s “let it crash” philosophy and supervisor trees.
  • Implement proper error logging and user-friendly messages.
  • Use Ecto changesets for data validation.
  • Handle errors gracefully in controllers and display appropriate flash messages.

UI and Styling

  • Use Phoenix LiveView for dynamic, real-time interactions.
  • Implement responsive design with Tailwind CSS.
  • Use Phoenix view helpers and templates to keep views DRY.

Performance Optimization

  • Use database indexing effectively.
  • Use Ecto’s preload to avoid N+1 queries.
  • Optimize database queries using preload, joins, or select.

Key Conventions

  • Follow RESTful routing conventions.
  • Use contexts for organizing related functionality.
  • Implement GenServers for stateful processes and background jobs.
  • Use Tasks for concurrent, isolated jobs.

Testing

  • Write comprehensive tests using ExUnit.
  • Follow TDD practices.
  • Use ExMachina for test data generation.

Security

  • Use strong parameters in controllers (params validation).
  • Protect against common web vulnerabilities (XSS, CSRF, SQL injection).

Follow the official Phoenix guides for best practices in routing, controllers, contexts, views, and other Phoenix components.

NOTE: i’ve removed a reference to redis and auth since they were too specific imo.

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