Tutorial
Provide a comprehensive and well-designed User Guide. (Be creative! An instructional video may work as well.)
API Documentation
Provide detailed API documentation, preferably, automatically built from source code documentation (use tools like doxygen, yard, rdoc, naturaldocs, etc).
Testing
Demonstrate that you followed best practises in software development so that other developers can modify, use and reuse your code. Provide more than one realistic test case. Examples of best practices are automated unit testing and documentation of test coverage, bug tracking facilities, documentation of releases and changes between releases.
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