Winpdb is compatible with CPython 2.3 or later (CPython is the official Python implementation). Winpdb is NOT compatible with Jython or IronPython.
The Winpdb GUI depends on wxPython 2.6.x or later but you can use rpdb2, the console version of the debugger, without wxPython.
Python Cryptography Toolkit (Optional)
Winpdb uses the Python Cryptography Toolkit to encrypt socket communication with the debugged script. Without the toolkit connections will be password-authenticated only.
Firewall Ports (For remote debugging)
When using Winpdb for remote debugging make sure any firewall on the way has TCP port 51000 open. Note that if port 51000 is taken Winpdb will search for an alternative port between 51000 and 51023.