Hi, Attached is a patch and some files required to build Hat on Windows. These superceed the ones I sent earlier. With this you get the following tools: hat-trans, exactly as per Linux hat-make, a new tool for windows, think hmake -hat but for Windows (and not as clever) hat-check, exactly as per Linux hat-cover, not very useful unless you do -hion and -hioff since the escape codes are turned off hat-stack, like Linux minus the syntax hilighting hat-observe, lots of escape code garbage, but you can still see the answers The tweaks are: ntohl, not on Windows fopen needs a "b" in the list of options no escape codes, try and eliminate them where possible The new files are: Makefile.bat, the root of the hat repo, serves as a Makefile on Windows - please rename Makefile.bad to .bat, because Gmail won't let me send a "dangerous executable" ntohl.h, for include ntohl.c, for src\hattools, provides the implementation of ntohl HatMake.hs, for src\hattools, the implementation of hat-make Most of the user visible changes are because of the lack of escape codes, which are used in the Linux versions to make a GUI out of the console. The Windows solution would just be to use the standard GUI, and turn the tools into slightly more abstract versions which can have the two interaction methods layered on top of them. I also want to change hat-cover to have an option to output HTML, possible combined with HsColour (modified to be a Haskell library as well as a program) so you can get syntax coloured and nicely highlighted Haskell code. Thanks Neil