4x4 reduction uses cubing.js 0.54.5, with a local adapter for entered cubies.
Project: https://github.com/cubing/cubing.js
Package license: MPL-2.0 OR GPL-3.0-or-later.
The application uses the library under its MPL-2.0 distribution option.

The library contains the three-phase 4x4 solver by Shuang Chen (cs0x7f),
ported through csTimer and cubing.js. Its upstream notice is preserved in
UPSTREAM-LICENSE.txt. The cubing.js project describes its library licensing at:
https://github.com/cubing/cubing.js#license

Local changes expose an entered-cubie reduction method and its forward moves.
They preserve the original scramble API. Complete modified files are published
alongside this notice as modified-cubing-source.js and modified-package.json.
The original package is available from npm as cubing@0.54.5. The published patch
is applied reproducibly by pnpm; no private application data is part of it.

MPL license text: LICENSE-MPL-2.0.txt
Modified source and patch: MPL-2.0, rubikscubesolver.org contributors, 2026.