[ianburrell]

I think you could make YAML safer and still support most usage by just preventing the deserializer from making any explicit native types. Just support the default types (string, list, map) and ignore all language specific tags. In fact, it looks like the core schema defined in the YAML spec would serve this purpose and would have similar types to JSON.

By making that the default schema, developers would have to explicitly request the dangerous "ruby" schema that makes arbitrary Ruby objects.