How did the Windows 95 user interface code get brought to the Windows NT code base?
SMRTR summary
Windows 95's user interface was integrated into Windows NT 4.0 through both teams working closely during development. The window manager features were reimplemented from scratch using Windows 95 code as reference, while Explorer and other components were directly ported and modified for Windows NT's Unicode system. The Windows NT team used protective coding techniques like #ifdef directives and special macros to ensure their changes wouldn't break the original Windows 95 code when merged back.
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