The original Bitcoin client includes a comment showing he used wxFormBuilder to generate the UI.
Not quite an AI code assistant — but it generated code nonetheless.
wxFormBuilder was a GUI designer for wxWidgets C++ toolkit and fairly common.
You could design the layouts then it would automatically generated the corresponding C++ code for the GUI components.
Satoshi prolly preferred this because it was also lightweight and had less dependences.
With version 0.5 on 21 November 2011, The Bitcoin Client(not yet called Core) introduced the QT user interface.
The QT stayed in the name of the client for a number of years.
The QT UI is still use this today by the Bitcoin Core client.
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