Versioning¶

ELANG keeps several independent version domains. A change in one does not imply a change in another. This separation lets the format, its schemas, each language release, and the tooling evolve at their own pace.

Version domains¶

The reader supports binary 0.1 only. Header/format.version's first two components must match the header major/minor, and the patch component cannot change the binary grammar.

The language version string is parsed as strict MAJOR.MINOR.PATCH with no leading zeros, and must equal the version suffix of the metadata.identifier URN exactly.

SDK / crate version¶

The Rust reference implementation's crate version is separate from the format domains and follows SemVer:

• MAJOR — a breaking public API change, or a change that alters previously valid accept/reject behavior.
• MINOR — backward-compatible features (new CLI flags, new read APIs).
• PATCH — backward-compatible fixes that do not change canonical bytes or accept/reject decisions.

A change in a format domain does not force an SDK major bump unless it breaks the public Rust API.

Changes that require extra care¶

Any change to canonical bytes, a locked rule, or normative data requires an approved design decision and, where relevant, regenerated golden hashes — even for an otherwise "patch" fix. Locked rules include the binary layout, the EPF/ELD grammars, the IPA/Unicode rules, and the canonicalization rules.

Pinned dependencies¶

For reproducibility, several inputs are pinned and do not drift with the host environment:

• Unicode 18.0.0 (first-party tables generated from the official UCD).
• IPA 2026 chart issue.
• libzstd 1.5.7 for canonical frames.
• The Rust toolchain and the full dependency set, via a committed lock file.