I wonder where this should fit in? It introduces itself as

> Data with an immutable schema.

But for what? I don't see a fit for APIs here, maybe config but there are already other languages that are perfectly suited for this job.

Also this feels more like some proposal than a serious attempt to build a new format. Java is widely used but I would at least expect such a new format to at least release with Java-/TypeScript, Go and Python libraries (personal perference: Rust too). But just a Java launch is at best a PoC.