Versioning

This page describes how YaFF is versioned and what stability to expect between releases.

Numbering Scheme

YaFF's version is major.minor.patch, read from the VERSION file at the repository root. The scheme leaves room for full semantic versioning, but YaFF is still pre-1.0.0: with only a C++ support today, the interface may still change as development continues.

Matching the Support Library and Generated Code

The generated code and the support library it is built against must be the exact same version. Every generated header bakes in the version it was produced with and compares it, at compile time, against the support library's YAFF_VERSION macro, so a mismatch is a compile error.

YAFF_VERSION is computed from that file as major * 10000 + minor * 100 + patch (so 0.1.0 is 100). When you upgrade YaFF, regenerate your code and rebuild everything that uses it.

Wire Format Stability

The wire format changes under a single rule: a new version may add new layouts, but never alters the encoding of an existing one. Two consequences follow:

• An existing layout's encoding is fixed, so a buffer that uses it stays readable by every later version (backward compatibility).
• A new layout is understood only by the version that introduced it and later ones, so an older support library cannot read a buffer that uses it (no forward compatibility for newly added layouts).

To keep rollouts safe, new layouts will be opt-in behind a feature flag, so producers do not start emitting one before every reader can handle it.