Here's a trick though: I got lazy (a bit) and did not write a full deserializer for Schema because this is busywork and not at all necessary at this stage. Instead, I've made the blueprint parameterized by a generic type <T>; which represents the type of the underlying blueprint's schema. When deserializing from JSON, we can default to 'Value' to get a free deserializer. Since all we're interested about is the program and the metadata (purpose and title) of a validator, it works nicely.
Serialization however expects a Blueprint<Schema>, and most of the functions operates over a Blueprint<Schema> anyway.
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