The electronic musician’s toolkit is increasingly characterized by fluidity between software, techniques, and genres. By combining two of the most exciting recent packages for MAX, CATART corpus-based concatenative synthesis (CBCS) and BACH: AUTOMATED COMPOSER’S HELPER, we propose a rich tool for real-time creation, storage, editing, re-synthesis, and transcription of concatenative sound. The modular structures of both packages can be advantageously recombined to exploit the best of their real-time and computer-assisted composition (CAC) capabilities. After loading a sample corpus in CATART, each grain, or unit, played from CATART is stored as a notehead in the bach.roll object along with its descriptor data and granular synthesis parameters including envelope and spatialization. The data is attached to the note itself (pitch, velocity, duration) or stored in user-defined slots than can be adjusted by hand or batch-edited using lambda-loops. Once stored, the contents of bach.roll can be dynamically edited and auditioned using CATART for playback. The results can be output as a sequence for synthesis, or used for CAC score-generation through a process termed Corpus-Based Transcription: rhythms are output with bach.quantize and further edited in bach.roll before export as a MUSICXML file to a notation program to produce a performer-readable score. Together these techniques look toward a concatenative DAW with promising capabilities for composers, improvisers, installation artists, and performers.