Tardis is a pre-processor which reconditions (precompiles) a marked-up unix shell command to generate a sequence of conditioned commands which it then launches on a cluster. The mark-up is added by the user to indicate the input(s) and output(s) of the command. Tardis splits input files into conditioned input chunks and will uncondition (join together) the output chunks to obtain the final outputs, with the sequence of conditioned commands referring to conditioned input and output filenames.