diff --git a/README.rst b/README.rst
index bc5015cad..46a38afdc 100644
--- a/README.rst
+++ b/README.rst
@@ -383,7 +383,7 @@ The following `command line arguments`_ can also be used to modify the defaults:
        versions that should be supported by Black's output. [default: per-file auto-
        detection]
 --formatter FORMATTER
-       Formatter to use for reformatting code
+       [black\|none\|ruff] Formatter to use for reformatting code. [default: black]
 
 To change default values for these options for a given project,
 add a ``[tool.darker]`` section to ``pyproject.toml`` in the project's root directory,
diff --git a/setup.cfg b/setup.cfg
index 87da4c762..1884182b9 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -47,6 +47,7 @@ darker =
 [options.entry_points]
 darker.formatter =
     black = darker.formatters.black_formatter:BlackFormatter
+    ruff = darker.formatters.ruff_formatter:RuffFormatter
     none = darker.formatters.none_formatter:NoneFormatter
 console_scripts =
     darker = darker.__main__:main_with_error_handling