1984,1985 Data Becker, Thomas Helbig & (c)1985 Abacus Software. BASIC 128 allows you to convert a BASIC program into a compiled machine language program for significant increases in speed.

The manual can be found here.

Update 8/14/2024 - This archive has been updated.  The original archive contained version 1.00 of BASIC 128, but it was broken.  This is now version 1.03 and a .g64 disk image with protection still in tact.  I have tested this on a real 128D and it's fully working.