Hi everyone! I'm the co-founder of Pianoshelf, and we're a team of CS students who built this in our spare time. This is our first time working with frontend MV*, so it was quite a learning curve as most of us were used to static languages taught in school (C++). Some parts are still clunky and need tests and refactoring (controller logic into directives, etc). The stack is (AngularJs, Django, nginx, Amazon S3). The frontend code at https://github.com/pianoshelf/pianoshelf-frontend if anyone is interested:

The idea came when I was looking for sheetmusic while learning to play the piano and found many websites difficult to use, or didn't have the features I wanted. Most of the content is from imslp.org and are copyright free. Suggestions are greatly appreciated!