dusty deck

n. Old software (especially applications) which one is obliged to remain
compatible with, or to maintain ( DP types call this legacy code , a term
hackers consider smarmy and excessively reverent). The term implies that the
software in question is a holdover from card-punch days. Used esp. when
referring to old scientific and number-crunching software, much of which was
written in FORTRAN and very poorly documented but is believed to be too
expensive to replace. See fossil ; compare crawling horror.

