Who says Linux should get all the open source apps? Successful cross-platform applications such as Firefox and OpenOffice.org reduce the barrier to switch from Windows to Linux, so what would it take to get BleachBit running on Windows?
BleachBit requires Python, PyGTK, and GTK. Though I never worked with GTK, I strategically these dependencies because they are cross platform and standard on most Linux distributions. However, installing this software stack on Windows is non-trivial. For example, GRAMPS requires the same stack, and the installation instructions require six installation packages totaling about 30MB—far too big and complex. Compare that to Linux where BleachBit is one package under 100KB because the dependencies are already there. Gourmet Recipe Manager seems to have fit all of PyGTK and friends in one Windows package of about 12MB: that could be tolerable but is still large.
Another option is writing the front end in native Windows code to eliminate the GTK+ dependency and help Windows users feel at home. (Firefox and OpenOffice.org use native widgets for the same reason.) Though maintaining two GUIs is not generally desirable, only 20% of the code is the PyGTK GUI, which is also modular, so this is feasible. Transmission (the BitTorrent client) maintains native GUIs for Linux, Windows, and Mac, but they probably have more developers. Using Python to access the BleachBit backend and to write the new Windows frontend could be accomplished with IronPython. On a whim, I tried to run a BleachBit unit test, which I was surprised to find passed on Windows 7 beta:
The startup was painfully slow and it looks like the unit test should have actually failed, but it was a pleasant surprise to see it get that far. It seems IronPython can even create .EXE's (with some dependencies).
Another option is wxPython: writing code once in Python creates native GUIs for Linux, Mac, Windows, and other systems. I have experience with wxWidgets (which wxPython uses), but there are still two problems. First, wxPython is not standard on Linux, and the dependencies for Linux and Windows are large (3-10MB). This is better for Windows than GTK, but it's a little worse for Linux.
Originally I considered many options including Python with GTK, C++ with wxWidgets, and C#.NET. There are simply no perfect choices for a high-level, cross-platform language with native GUI that is already installed standard on Linux and Windows. C#.NET is the closest choice, but again there are pros and cons. It's relatively standard on Windows and Linux (coming standard on Fedora, Ubuntu, and others), but some Linux users are allergic to it because of the connection with Novell and Microsoft. Worse of all, the GTK GUI is not standard on Windows, and on Linux it GTK is practically a necessity because Mono WinForms is so ugly.
In conclusion, BleachBit is not coming to Microsoft Windows soon. BleachBit will continue to focus on Linux, and the biggest short-term platform change will be supporting the new Debian 5, released just yesterday.
Future article: BleachBit on Windows Vista (May 2009).