add CONTRIBUTING.md

Author: Cap32

CONTRIBUTING.md

@@ -0,0 +1,36 @@
+# Contributing
+
+## Issues
+
+Please provide a minimal, reproducible test-case.
+
+
+## Pull Requests
+
+Follow the instructions on the Pull Request Template (shown when you open a new PR) and make sure you've done the following:
+
+- [ ] Add & update tests
+- [ ] Ensure CI is passing (lint, tests)
+- [ ] Update relevant documentation and/or examples
+
+
+## Setup
+
+This package uses [yarn](https://yarnpkg.com) for development dependency management. Ensure you have it installed before continuing.
+
+```sh
+yarn
+```
+
+## Running Tests
+
+```sh
+yarn test
+```
+
+
+## Building
+
+```sh
+yarn build
+```

README.md

@@ -53,6 +53,10 @@ stringify({ foo: 'bar', baz: ['qux', 'quux'], corge: '' });
 /* returns 'foo=bar&baz=qux&baz=quux&corge=' */
 ```
 
+## Contributing
+
+[Contributing](/CONTRIBUTING.md)
+
 
 ## License