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CONTRIBUTING.md

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+# Contributing to Lazy Load
+
+## Only one feature or change per pull request
+
+Make pull requests only one feature or change at the time. For example you have fixed a bug. You also have optimized some code. Optimization is not related to a bug. These should be submitted as separate pull requests. This way I can easily choose what to include. It is also easier to understand the code changes. Commit messages should be descriptive and full sentences.
+
+Do not commit minified versions. Do not touch the version number. Make the pull requests against [1.9.x branch](https://github.com/tuupola/jquery_lazyload/commits/1.9.x).
+
+## Write meaningful commit messages
+
+Proper commit message is full sentence. It starts with capital letter but does not end with period. Headlines do not end with period. The GitHub default `Update filename.js` is not enough. When needed include also longer explanation what the commit does.
+
+```
+Capitalized, short (50 chars or less) summary
+
+More detailed explanatory text, if necessary.  Wrap it to about 72
+characters or so.  In some contexts, the first line is treated as the
+subject of an email and the rest of the text as the body.  The blank
+line separating the summary from the body is critical (unless you omit
+the body entirely); tools like rebase can get confused if you run the
+two together.
+```
+
+When in doubt see Tim Pope's blogpost [A Note About Git Commit Messages](http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html)
+
+## Follow the existing coding standards
+
+When contributing to open source project it is polite to follow the original authors coding standars. They might be different than yours. It is not a holy war. Just follow then original.
+
+```javascript
+var snake_case = "something";
+
+function camelCase(options) {
+}
+
+if (true !== false) {
+    console.log("here be dragons");
+}
+```
+
+## Make sure tests pass
+
+After you change some code make sure all the test still pass. You can run tests from the commandline with the following:
+
+```
+npm install
+grunt test
+```
+
+Or you can also open the [test runner](https://github.com/tuupola/jquery_chained/blob/master/test/SpecRunner.html) in browser.