In this episode of Subscribe, Clemens introduces JSON Structure, a pragmatic data definition language designed to address the architectural shortcomings of JSON Schema. Consisting of a core specification and six companion extensions, the project shifts focus from simple validation to robust structural modeling for programming languages and databases. Key features include a rich system of extended primitive types like 128-bit integers and UUIDs, first-class compound types such as sets, maps, and tuples, and a disciplined approach to type reuse through namespaces and strict $ref rules. By decoupling structural definition from pattern-based validation and introducing an explicit import model, JSON Structure provides a deterministic, tooling-friendly alternative for high-interoperability data interchange