A system for producing secure data management software, comprising at least one hardware processor adapted to: receive a plurality of data patterns, each comprising at least one data field identifier selected from a set of protected data field identifiers of at least one data repository, at least one output target, and an access instruction; identify in a plurality of computer instructions of the data management software one or more forbidden output instructions by matching one or more reaching definitions of some of the plurality of computer instructions with one or more of the plurality of data patterns; and remove the one or more forbidden output instructions from the plurality of computer instructions.