A simulation of the infamous WW2 era cipher machine.
The simulator is written in the JavaScript programming language and has very good test coverage.
cjw6k wrote this software while attending Summerside Makerspace in June, 2016. It was published on the makerspace website and github account. Later, it was added to Wikipedia as the first such simulation to support the configurable reflector, the UKW-D. The makerspace is no longer operating nor maintaining the software, so it's maintained here. The copyright has been updated to list the originating author rather than the organization, and the license has been updated from Apache to MIT.