Hi Vortex team and community 👋

I've been building a pure-Java implementation of the Vortex format: dfa1/vortex-java.

What it is:

• 100% Java, no JNI, no sun.misc.Unsafe — uses the FFM API (MemorySegment/Arena) for zero-copy mmap
  reads
• Reads and writes all 35 encodings in the v0.72.0 S3 fixture set, verified against the Rust JNI reader
  as a test oracle
• The vortex-jni JAR is 258 MB; this is <1 MB pure Java — embeds
  anywhere, debugs with standard JVM tooling
• The goal is a fully functional interoperable library with a GitHub organisation around it
• When the Vector API ships, the plan is to use SIMD to speed up the hot encode/decode paths

A few questions:

1. Is there a detailed format specification, or plans to write one? Right now the Rust source is the
   ground truth — encoding metadata (e.g. RunEndMetadata, ZstdMetadata) has no upstream .proto file, and
   some wire-format invariants are implicit in the implementation. A spec (even a minimal one) would make
   third-party implementations much more robust.
2. Any undocumented invariants worth knowing — things the Rust implementation assumes but doesn't
   validate?
3. I noticed the Go implementation (vortex-go) as well — good to see the ecosystem growing. Do you also have plans for non-JNI version for Java?

Happy to contribute back anything useful.
Thanks for building such a well-designed format!