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+# Contributing
+
+> This project has a [Code of Conduct][coc].  By interacting with this
+> repository, organisation, or community you agree to abide by its terms.
+
+Hi!  👋 Exciting that you’re interested in contributing!  Before doing so, take
+a moment to read the following guidelines.  And thanks for contributing to
+**unified**!  👏👌✨
+
+Before anything else: people involved with this project often do so for fun,
+next to their day job: you are not entitled to free customer service.
+
+## Table of Contents
+
+*   [Ecosystem](#ecosystem)
+*   [Questions](#questions)
+*   [Contributions](#contributions)
+    *   [Improve documentation](#improve-documentation)
+    *   [Improve issues](#improve-issues)
+    *   [Give feedback on issues](#give-feedback-on-issues)
+    *   [Write code](#write-code)
+*   [Submitting an issue](#submitting-an-issue)
+*   [Submitting a pull request](#submitting-a-pull-request)
+*   [Resources](#resources)
+
+## Ecosystem
+
+The ecosystem consists of several organisations and separate projects: most of
+them are tiny, and many of them have a utility
+([`mdast-util-to-hast`][mdast-util-to-hast]), a plugin
+([`remark-rehype`][remark-rehype]), and relate to an ecosystem
+([`remark`][remark]).  Try and pick the right place to contribute to so we can
+help you faster.
+
+## Questions
+
+Please chat and ask questions on Gitter!  Jump in there and lurk, talk to us,
+and help others.
+
+*   [**unified**](https://gitter.im/unifiedjs/Lobby)
+    — Topics relating to [**unified**][unified] in general
+*   [**vfile**](https://gitter.im/vfile/Lobby)
+    — Topics relating to [**vfile**][vfile]: virtual files
+*   [**syntax-tree**](https://gitter.im/syntax-tree/Lobby)
+    — Topics relating to [**syntax-tree**][syntax-tree] and [**unist**][unist]
+*   [**remark**](https://gitter.im/wooorm/remark)
+    — Topics relating to [**remark**][remark]s ecosystem, markdown,
+    and [**mdast**][mdast]
+*   [**rehype**](https://gitter.im/wooorm/rehype)
+    — Topics relating to [**rehype**][rehype]s ecosystem, HTML,
+    and [**hast**][hast]
+*   [**retext**](https://gitter.im/wooorm/retext)
+    — Topics relating to [**retext**][retext]s ecosystem, natural language,
+    and [**nlcst**][nlcst]
+
+## Contributions
+
+There’s several ways to contribute, not just by writing code.
+
+### Improve documentation
+
+As a user of this project you’re perfect for helping us improve our docs.
+Typo corrections, error fixes, better explanations, new examples, etcetera.
+Anything!
+
+### Improve issues
+
+Some issues lack information, aren’t reproducible, or are just incorrect.
+Help make them easier to resolve.
+
+### Give feedback on issues
+
+We’re always looking for more opinions on discussions in the issue tracker.
+
+### Write code
+
+Code contributions are very welcome.  It’s often good to first create an issue
+to report a bug or suggest a new feature before creating a pull request to
+prevent you from doing unnecessary work.
+
+## Submitting an issue
+
+*   The issue tracker is for issues.  Use chat for support
+*   Search the issue tracker (including closed issues) before opening a new
+    issue
+*   Ensure you’re using the latest version of projects
+*   Use a clear and descriptive title
+*   Include as much information as possible: steps to reproduce the issue,
+    error message, version, operating system, etcetera
+*   The more time you put into an issue, the more we will
+*   The best issue report is a [failing test][unit-test] proving it
+
+## Submitting a pull request
+
+*   Non-trivial changes are often best discussed in an issue first, to prevent
+    you from doing unnecessary work
+*   For ambitious tasks, you should try to get your work in front of the
+    community for feedback as soon as possible
+*   New features should be accompanied with tests and documentation
+*   Don’t include unrelated changes
+*   Lint and test before submitting code by running `$ npm test`
+*   Write a convincing description of why we should land your pull request:
+    it’s your job to convince us
+
+## Resources
+
+*   [How to Contribute to Open Source](https://opensource.guide/how-to-contribute/)
+*   [Making your first contribution](https://medium.com/@vadimdemedes/making-your-first-contribution-de6576ddb190)
+*   [Using Pull Requests](https://help.github.com/articles/about-pull-requests/)
+*   [GitHub Help](https://help.github.com)
+
+[coc]: https://github.com/unifiedjs/unified/blob/master/code-of-conduct.md
+
+[vfile]: https://github.com/vfile
+
+[syntax-tree]: https://github.com/syntax-tree
+
+[unist]: https://github.com/syntax-tree/unist
+
+[mdast]: https://github.com/syntax-tree/mdast
+
+[nlcst]: https://github.com/syntax-tree/nlcst
+
+[hast]: https://github.com/syntax-tree/hast
+
+[unified]: https://github.com/unifiedjs/unified
+
+[remark]: https://github.com/wooorm/remark
+
+[retext]: https://github.com/wooorm/retext
+
+[rehype]: https://github.com/wooorm/rehype
+
+[mdast-util-to-hast]: https://github.com/syntax-tree/mdast-util-to-hast
+
+[remark-rehype]: https://github.com/wooorm/remark-rehype
+
+[unit-test]: https://twitter.com/sindresorhus/status/579306280495357953