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README.md

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 # Monaco CSS
 
-CSS language plugin for the Monaco Editor.
+CSS language plugin for the Monaco Editor. It provides the following features when editing CSS, LESS and SCSS files:
+* Code completion
+* Hovers
+* Validation: Syntax errors and linting
+* Find definition, references & highlights for symbols in the same file
+* Document Symbols
+
+Linting an be configured through the API. See ([here](https://github.com/Microsoft/monaco-css/blob/master/src/monaco.d.ts) for the API that the
+CSS plugin offers to configure the CSS/LESS/SCSS language support.
+
+Internally the CSS plugin uses the [vscode-css-languageservice](https://github.com/Microsoft/vscode-css-languageservice)
+node module, providing the implementation of the functionally listed above. The same module is also used
+in [Visual Studio Code](https://github.com/Microsoft/vscode) to power the CSS, LESS and SCSS editing experience.
+
+## Installing
+
+This npm module is bundled and distributed in the [monaco-editor](https://www.npmjs.com/package/monaco-editor) npm module.
+
+## Dev: cheat sheet
+
+* initial setup with `npm install .`
+* compile with `npm run watch`
+* bundle with `npm run prepublish`
+
+## Dev: Running monaco-css from source
+
+* clone https://github.com/Microsoft/monaco-css in `$/src/monaco-css`
+* run `$/src/monaco-css> npm run watch`
+* clone https://github.com/Microsoft/monaco-editor in `$/src/monaco-editor`
+* run `$/src/monaco-editor> npm run simpleserver`
+* open http://localhost:8080/monaco-editor/test/?monaco-css=dev
+
+### [Optional] Running monaco-editor-core from source
+
+* this is only needed when you want to make changes also in `monaco-editor-core`.
+* clone https://github.com/Microsoft/vscode in `$/src/vscode/`
+* run `$/src/vscode> gulp watch`
+* open http://localhost:8080/monaco-editor/test/?monaco-css=dev&editor=dev
 
 
 ## Installing