Hi Günther Congratulations!
You might find this article useful. Though it only mentions one particular system Armadillo, there are a number of good tips like releasing updates frequently so the binaries change, and the author is well regarded in "micro software" circles. http://www.kalzumeus.com/2006/09/05/everything-you-need-to-know-about-registration-systems/ GHC binaries do contain quite a lot of textual information. Where functions work with registration codes you ought to cloak their names and maybe add a dummy API to throw crackers off the scent. Best wishes Stephen _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe