STEP (ISO 10303) development environment which supports the validation of STEP data populations via EXPRESS (ISO 10303-11) schemata and the transformation of STEP data populations from one schema to another via EXPRESS-X (ISO 10303-14) schemata.
STEP ToyBox is a project which develops various small applications for processing EXPRESS (ISO 10303-11) schemas and/or STEP Part 21 (ISO 10303-21) data files. Some are commandline only while others are GUI based.