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+# Add Languages and Beautifiers
+
+Please contribute with a Pull Request and add your favourite languages and beautifiers.
+
+## How to add a Language:
+
+1. Create a new Language file in https://github.com/Glavin001/atom-beautify/tree/master/src/languages
+2. Configure the new language. Example for `JavaScript` language: https://github.com/Glavin001/atom-beautify/blob/master/src/languages/javascript.coffee#L8
+  - `name` - name of Language
+  - `namespace` - used as a prefix for scoping the options, such as option `indent_size` becomes `js_indent_size` for `JavaScript` language with namespace `js`
+  - `grammars` - array of supported grammars. Used with `extensions` to determine if this file is this language or not. Grammars are prioritized over extensions, such that the grammar `JavaScript` is recognized before `js` and the beautifier with the same grammar as the file will be used over another that does not support the grammar and only the extension.
+  - `extensions` - array of of extensions, without `.` (dot), such that `.js` is `js`. Used to determine if a file is this language. Useful if there is no supported grammar in Atom for this language.
+  - `options` - I'd recommend looking at https://github.com/Glavin001/atom-beautify/blob/master/src/languages/javascript.coffee#L30 for examples.
+3. Add the language file to the list of language names. For instance, `c-sharp.coffee` file becomes `c-sharp`. See https://github.com/Glavin001/atom-beautify/blob/master/src/languages/index.coffee#L21
+Now your Language is available and can be detected and beautifiers can support it.
+
+## How to add a Beautifier for a Language
+
+1. Create a new [beautifier](https://github.com/Glavin001/atom-beautify/blob/master/src/beautifiers/beautifier.coffee) subclass in https://github.com/Glavin001/atom-beautify/tree/master/src/beautifiers directory
+2. Implement beautifier:
+  - See examples of beautifiers:
+    - Prettydiff is a good example of complex options: https://github.com/Glavin001/atom-beautify/blob/master/src/beautifiers/prettydiff.coffee
+    - PHP-CS-Fixer is a good example of a CLI beautifier with arguments: https://github.com/Glavin001/atom-beautify/blob/master/src/beautifiers/php-cs-fixer.coffee#L15-L39
+  - `options` - the key represents the Language's name. The value could be `true` (supports all options), `false` (supports language, with no options), or an `object` whose keys are option keys and values are complex mappings. If you need to use these, let me know. `true` is probably what you want.
+  - The `beautify` function should return a `Promise` (use `@Promise` as shown). The arguments passed are: `text`, the source code from Atom's Text Editor, `language` is a string of the language's name (`JavaScript`), and `options` is an object of all of the options in their form as described by your Language definition (see `Configure the new language` above).
+3. Add beautifier to list of `beautifierNames`: https://github.com/Glavin001/atom-beautify/blob/master/src/beautifiers/index.coffee#L34
+4. Add test example files in https://github.com/Glavin001/atom-beautify/tree/master/examples
+  - You can put your test in `nested-jsbeautifyrc` directory, https://github.com/Glavin001/atom-beautify/tree/master/examples/nested-jsbeautifyrc
+  - create a new directory for your tests, named something like `JavaScript`
+  - `original` and `expected` directory containing files that are named the same. Prefix underscore (`_`) disables a test. See https://github.com/Glavin001/atom-beautify/tree/master/examples/simple-jsbeautifyrc/php/original for instance.
+  - change any options you need in your namespace, such as `js`, in https://github.com/Glavin001/atom-beautify/blob/master/examples/nested-jsbeautifyrc/.jsbeautifyrc
+  - Run tests in Atom with command `Window: Run package spec`
+
+I have to go. Let me know if you have any questions!