License
Puzzle Hub uses no external data sources. All puzzles are generated in your browser by an in-house seeded backtracking solver with technique-based difficulty rating.
Data Source
There is no third-party data to attribute. Puzzles are produced by the in-browser solver in this repository — no scraped or imported content, no user-submitted boards.
License Terms
Generated puzzle data is released without restriction — feel free to play, share, or remix individual boards. Site code (UI, solver, generator) is part of the Mono Hub project and follows that project's source license.
Processing
Each puzzle is generated by removing cells from a fully-filled board, then verifying unique solvability and rating the required techniques (naked single, hidden single, naked pair, …) to assign a difficulty profile. Boards that don't fit the profile are discarded and the solver retries with the next seeded variant — only accepted boards are shown.