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CONTRIBUTING.md

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+# Contributing to Electron
+
+:+1::tada: First off, thanks for taking the time to contribute! :tada::+1:
+
+The following is a set of guidelines for contributing to Electron.
+These are just guidelines, not rules, use your best judgment and feel free to
+propose changes to this document in a pull request.
+
+## Submitting Issues
+
+* You can create an issue [here](https://github.com/atom/electron/issues/new),
+but before doing that please read the notes below and include as many details as
+possible with your report. If you can, please include:
+  * The version of Electron you are using
+  * The operating system you are using
+  * If applicable, what you were doing when the issue arose and what you
+  expected to happen
+* Other things that will help resolve your issue:
+  * Screenshots and animated GIFs
+  * Error output that appears in your terminal, dev tools or as an alert
+  * Perform a [cursory search](https://github.com/issues?q=+is%3Aissue+user%3Aatom)
+  to see if a similar issue has already been submitted
+
+## Submitting Pull Requests
+
+* Include screenshots and animated GIFs in your pull request whenever possible.
+* Follow the CoffeeScript, JavaScript, C++ and Python [coding style defined in docs](/docs/development/coding-style.md).
+* Write documentation in [Markdown](https://daringfireball.net/projects/markdown).
+* Use short, present tense commit messages. See [Commit Message Styleguide](#git-commit-messages-styleguide).
+
+## Styleguides
+
+### General Code
+
+* End files with a newline.
+* Place requires in the following order:
+  * Built in Node Modules (such as `path`)
+  * Built in Electron Modules (such as `ipc`, `app`)
+  * Local Modules (using relative paths)
+* Place class properties in the following order:
+  * Class methods and properties (methods starting with a `@`)
+  * Instance methods and properties
+* Avoid platform-dependent code:
+  * Use `require('fs-plus').getHomeDirectory()` to get the home directory.
+  * Use `path.join()` to concatenate filenames.
+  * Use `os.tmpdir()` rather than `/tmp` when you need to reference the
+    temporary directory.
+* Using a plain `return` when returning explicitly at the end of a function.
+  * Not `return null`, `return undefined`, `null`, or `undefined`
+
+### Git Commit Messages
+
+* Use the present tense ("Add feature" not "Added feature")
+* Use the imperative mood ("Move cursor to..." not "Moves cursor to...")
+* Limit the first line to 72 characters or less
+* Reference issues and pull requests liberally
+* Consider starting the commit message with an applicable emoji:
+  * :art: `:art:` when improving the format/structure of the code
+  * :racehorse: `:racehorse:` when improving performance
+  * :non-potable_water: `:non-potable_water:` when plugging memory leaks
+  * :memo: `:memo:` when writing docs
+  * :penguin: `:penguin:` when fixing something on Linux
+  * :apple: `:apple:` when fixing something on Mac OS
+  * :checkered_flag: `:checkered_flag:` when fixing something on Windows
+  * :bug: `:bug:` when fixing a bug
+  * :fire: `:fire:` when removing code or files
+  * :green_heart: `:green_heart:` when fixing the CI build
+  * :white_check_mark: `:white_check_mark:` when adding tests
+  * :lock: `:lock:` when dealing with security
+  * :arrow_up: `:arrow_up:` when upgrading dependencies
+  * :arrow_down: `:arrow_down:` when downgrading dependencies
+  * :shirt: `:shirt:` when removing linter warnings