The 32 bit version appears to be compiled with Delphi 2 - yes, this is an OLD version (the first 32 bit version) - but this is what the TC author himself states.

As a result, the 32 bit version executable is small and efficient. And, honestly, you can write a nice Unicode software without using generics and all the new Delphi features...

When looking at the 64 bit supplied version, it was obvious to me that even if the tool was behaving the same as the 32 bit version (fast and native user interface), the gears were not the same. It seems to have been compiled with the great Open Source Free Pascal Compiler - using not the VCL, but the cross-platform Lazarus project. I do not know if the LCL components where used, or some Total Commander-custom components (which I think is more than probable, knowing Ghisler's skill and hand-tuning abilities).

It is even clear if you look at the application history:

14.07.10 Added: Start work on conversion to Lazarus/Free Pascal in preparation for 64-bit version
As I wrote some time ago in this blog, FPC team published a 64 bit compiler using the Delphi/object pascal language in 2006. Whereas the "official" Win64 support just appeared this year, with Delphi XE2.

Christian Ghisler is working with FPC for a lot of time for the PocketPC (... and now Android!) freeware versions of his tool.

I'm very happy to see such a world-wide spread application using FPC and Lazarus tandem. There are open source alternatives to FireMonkey and Delphi XE2. Not a feature-like, but with another architecture, another rendering, another coding spirit, another cross-platform abilities, another mind openness... Even Delphi is using FPC as compiler when targeting iOS.

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