Update README.md

README.md

@@ -10,7 +10,8 @@
 [Menu Definition](#menu-definition)\
 [Item Types](#item-types) \
 [API](#api) \
-[Customize](#customize)
+[Customize](#customize) \
+[Contributing](#contributing)
 
 ## Screenshot
 ![Screenshot](https://raw.githubusercontent.com/nkappler/ctxmenu/master/docs/features.png)
@@ -236,3 +237,17 @@ ctxmenu.js uses the following css classes which you might want to overwrite:
 .ctxmenu li.interactive /* any interactive item (anchor, action item, submenu)*/
 .ctxmenu li.submenu     /* any menu item that has a submenu */
 ```
+
+## Contributing
+You can find the source code in the `src/` directory and the files for manual testing in the `test/` directory.
+> ⚠ Don't change any JavaScript files manually, as those changes will be overwritten by the build!
+
+### Test your changes
+Please test your changes before opening a PR. To test your changes locally, run `npm run build`. This will compile the typescript source files
+and update the files in the `standalone/` and `docs/` directories. You can now open the `docs/index.html` file in your browser to test your changes.
+
+### Adding Commits
+Currently, the build pipeline updates all javascript files simultaneously, including those used for the demo website and downloads.
+Those files should be kept in sync with the releases however.
+Please only commit changes to the typescript source files, if possible. If you need to touch other files as well, please add a note in the PR explaining why.
+I am working on an update for the build pipeline to address this manual step... 🙂