Cryptkit - a Tcl cryptographic toolkit Steve Landers Digital Smarties This paper describes the design and implementation of Cryptkit - a Tcl extension that provides a powerful toolkit that makes adding encryption and authentication services to Tcl applications straightforward - even for inexperienced crypto programmers. Cryptkit contains an abstracted binding to the Cryptlib security toolkit, plus a number of other features including an interface to Tcl channels, Tcllib cryptographic functions and an implementation of the recently endorsed X9.95 Trusted Time Stamp Management and Security standard.