RegexKit 0.6 for Mac was available as a free download on our application library. Our built-in antivirus checked this Mac download and rated it as virus free. The program lies within Developer Tools, more precisely General.
From the developer:
RegexKit is an Objective-C framework for regular expressions: Support for Mac OS X Cocoa and GNUstep. Mac OS X 10.4 or later required. Mac OS X Universal Binary, including 64-bit support on Mac OS X 10.5. No sub-classing required. Seamlessly adds regular expression support to all NSArray, NSDictionary, NSSet, and NSString Foundation objects with a rich set of Objective-C category additions. Unicode enabled.