Ultrakit - A Programmer's Toolkit by Zach Townsend (Alpha Omega, 1986) - ULTRAKIT adds nearly 30 commands to the standard Commodore Basic, for use in developing your own  programs. It includes commands for debugging BASIC programs, for listing to the printer, for altering and checking blocks of memory, as well as a fully-fledged multicolour Character Editor and Designer.

This archive contains a .TAP file instead of a .D64.  I was unable to convert it using FinalTAP because it isn't a BASIC program and has a non-standard loader.  You can easily use this in CCS64 or the VICE emulator.  Thanks to Green_Bert over at the Lemon64 forum for sharing this and the manual.