If your schema is dynamic, in most languages there isn't much you can do, but at least in python Q(name=contains('k')) it is not particularly more complex

If your schema is dynamic, in most languages there isn't much you can do, but at least in python Q(name=contains('k')) it is not particularly more complex to write and certainly more composable, extensible and checkable. Alternatively go full eval and do Q("'k' in name")