Plagiarism Guard was a plagiarism detection software written in Python 3 and Django back in 2014. It could either scan a webpage URL, or an uploaded document (.docx, .pptx, .txt et al) and then it would ‘go hunting’ for duplicate content. The source code for this project exists on Github, and is explained in more detail on this site.
A user’s account dashboard, showing general scan results in graphs (powered by Chart.js):
A summary of plagiarism results for various resources:
A set of plagiarism results from scanning a particular PDF:
A (completely over-complicated!) explanation of the order form for end users:
An explanation of the ‘bulk URL import’ feature of the order form: