Credo is a static code analysis tool for the Elixir language with a focus on teaching and code consistency.

It can show you refactoring opportunities in your code, complex code fragments, warn you about common mistakes, show inconsistencies in your naming scheme and - if needed - help you enforce a desired coding style.

The easiest way to add Credo to your project is by using Mix.

Add :credo as a dependency to your project's mix.exs:

defp deps do
  [
    {:credo, "~> 1.6", only: [:dev, :test], runtime: false}
  ]
end

And run:

$ mix deps.get

$ mix credo

Documentation is available on Hexdocs

Some IDEs and editors are able to run Credo in the background and mark issues inline.

• IntelliJ Elixir - Elixir plugin for JetBrains IDEs (IntelliJ IDEA, Rubymine, PHPStorm, PyCharm, etc)
• linter-elixir-credo - Package for Atom editor (by @smeevil)
• Elixir Linter (Credo) - VSCode extension (by @pantajoe)
• flycheck - Emacs syntax checking extension
• kakoune - Config for linting support in Kakoune editor
• Neovim via null-ls - diagnostics builtin

• Codacy - checks your code from style to security, duplication, complexity, and also integrates with coverage.
• SourceLevel - tracks how your code changes over time and have this information accessible to your whole team.
• Stickler CI - checks your code for style and best practices across your entire stack.

1. Fork it!
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request

René Föhring (@rrrene)

Credo is released under the MIT License. See the LICENSE file for further details.