We make Hamilton C shell. Hamilton Laboratories is an independent software vendor (ISV) selling tools to professional software developers since 1988. We are the developer and publisher of Hamilton C shell, an original work reimagining the Unix C shell as a modern interactive language with procedures, block-structured local variables, floating point and so on. The internal architecture is completely multithreaded with separate top-down recursive descent compiler and execution units. Includes the rest of the usual suspects including more, grep, ls, mv, cp, rm, head, tail, diff, chown, tar, su and sudo (yes! really!) from scratch on Windows. Plays nice, all the executables are signed, follows Windows conventions and works fine with but beats the pants off Cygwin.