Access the source code
Bingo is completely open source.
To access the source in versions 1.1 to 1.3, click on the "Set" menu and click on "Developer's mode". The passwords are in place to avoid inexperienced modification of the source code.
In 1.1 and 1.2, the password is "blubber".
In 1.3, the password is "sunny".
2.0 features a password-free open source, but protects you from unwanted changes using a new method. Details are found in-program through the Dev menu.