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+# ReDoc Contributing Guide
+
+Hi! We're really excited that you are interested in contributing to ReDoc. Before submitting your contribution though, please make sure to take a moment and read through the following guidelines.
+
+- [Issue Reporting Guidelines](#issue-reporting-guidelines)
+- [Pull Request Guidelines](#pull-request-guidelines)
+- [Development Setup](#development-setup)
+- [Project Structure](#project-structure)
+
+## Issue Reporting Guidelines
+- Before filing a new issue, try to make sure your problem doesn’t already exist.
+- The best way to get your bug fixed is to provide a reduced test case.
+
+## Pull Request Guidelines
+Before submitting a pull request, please make sure the following is done:
+
+1. Fork the repository and create your branch from master.
+2. Run `yarn` in the repository root.
+3. If you’ve fixed a bug or added code that should be tested, add tests!
+4. Ensure the test suite passes (`yarn test`). Tip: `yarn test --watch TestName` is helpful in development.
+5. Format your code with prettier (`yarn prettier`).
+
+## Development Setup
+
+You will need [Node.js](http://nodejs.org) at `v8.0.0+` and [Yarn](https://yarnpkg.com/en/) at `v1.2.0+`
+
+After cloning the repo, run:
+
+```bash
+$ yarn install # or yarn
+```
+
+### Commonly used NPM scripts
+
+``` bash
+# dev-server, watch and auto reload playground
+$ yarn start
+
+# start playground app in production environement
+$ yarn start:prod
+
+# runt tslint
+$ yarn lint
+
+# try autofix tslint issues
+$ yarn lint --fix
+
+# run unit tests
+$ yarn unit
+
+# run e2e tests
+$ yarn e2e
+
+# open cypress UI to debug e2e test
+$ yarn cy:open
+
+# run the full test suite, include linting / unit / e2e
+$ yarn test
+
+# prepare bundles
+$ yarn bundle
+
+# format the code using prettier
+$ yarn prettier
+
+# auto-generate changelog
+$ yarn changelog
+```
+
+There are some other scripts available in the `scripts` section of the `package.json` file.
+
+## Project Structure
+
+- **`demo`**: contains project demo with demo specs and HMR playground used in development
+
+  - `demo/playground`: HMR Playground used in development
+
+- **`docs`**: contains extra docs (linked from README.md)
+
+- **`e2e`**: contains e2e tests. The e2e tests are written and run with [Cypress](https://www.cypress.io/).
+
+- **`perf`**: contains basic perf benchmark. Not ready yet
+
+- **`src`**: contains the source code. The codebase is written in Typescript. CSS styles are managed with [Styled components](https://www.styled-components.com/). State is managed by [MobX](https://github.com/mobxjs/mobx)
+
+  - **`src/common-elements`**: containts common Styled elements or components used in multiple places
+  - **`src/components`**: contains main visual components
+  - **`src/services`**: contains different services used by ReDoc including MobX stores
+  - **`src/services/models`**: contains classes for OpenAPI entities (e.g. Response, Operations, etc)
+  - **`src/types`**: contains extra typescript typings including OpenAPI doc typings
+  - **`src/utils`**: utility functions
+  - **`src/styled-components.ts`**: - reexprots styled-components with proper typescript annotations using theme
+  - **`src/theme.ts`**: - default theme (colors, fonts, etc) used by all the components