The UNRAVEL project is a computational process model of systematic procedural error in a continuous task, Altmann & Trafton's UNRAVEL task. Based on Tamborello & Trafton's (2013a & b) model of postcompletion, anticipation, and perseveration error in a routine procedural non-continuous task. Developed with ACT-R6 (r1227), boost-chunks module 10 (may be made available upon request), spacing-effect module (ACT-R extras), & new-threads 2.0a (ACT-R extras), & Mike Byrne's misc-lib and seq-math libraries (included for convenience).