mix-master

name	mix-master
description	Manage Elixir dependencies at runtime using Mix

MixMaster Skill

You can manage Elixir project dependencies using this skill.

Adding a dependency

When you need to add a new Elixir package to the project:

1. Read the current mix.exs file to understand the existing dependencies
2. Edit mix.exs to add the dependency to the deps() function:

   defp deps do
     [
       {:new_package, "~> 1.0"}
       # ... other deps
     ]
   end
   

3. Run shell tool with command: mix deps.get to fetch the new dependency
4. Run shell tool with command: mix compile to compile and verify

Common Mix commands

Dependency management

• mix deps.get - Fetch dependencies
• mix deps.update package_name - Update a specific package
• mix deps.clean --all - Clean all dependencies (use carefully)
• mix deps.tree - Show dependency tree

Project operations

• mix compile - Compile the project
• mix compile --warnings-as-errors - Compile with strict mode
• mix clean - Clean build artifacts

Testing

• mix test - Run all tests
• mix test test/path/to/file_test.exs - Run specific test file
• mix test test/path/to/file_test.exs:42 - Run test at specific line
• mix test --failed - Re-run only failed tests

Code quality

• mix format - Format code according to .formatter.exs
• mix format --check-formatted - Check if code is formatted
• mix credo - Run static code analysis (if credo is installed)

Phoenix specific

• mix phx.routes - List all Phoenix routes
• mix phx.server - Start Phoenix server
• mix phx.gen.context - Generate context
• mix phx.gen.live - Generate LiveView

Database (Ecto)

• mix ecto.create - Create database
• mix ecto.migrate - Run migrations
• mix ecto.rollback - Rollback last migration
• mix ecto.reset - Drop, create, migrate, and seed database

Best practices

1. Always read mix.exs first before adding dependencies to avoid duplicates
2. Check compilation after adding new dependencies
3. Run tests to ensure new dependencies don't break existing code
4. Format code after making changes with mix format
5. Update documentation if you add a significant dependency

Example workflow

# User asks: "Add the Jason library for JSON parsing"

# Step 1: Read current mix.exs
read_file("mix.exs")

# Step 2: Edit to add Jason
edit_file(
  path: "mix.exs",
  old_string: "defp deps do\n    [",
  new_string: "defp deps do\n    [\n      {:jason, \"~> 1.4\"},"
)

# Step 3: Fetch dependency
shell("mix deps.get")

# Step 4: Compile to verify
shell("mix compile")