0.4.0 — Five vNext RFCs, Zero Breakage

2026-08-19 · additive · every 0.3.0 document stays valid (regression-asserted)

0.4.0 is the first delivery of the vNext roadmap: the bet that the open standard should be a strict superset of what its most advanced implementations already do — so migrating to it is an upgrade, never a compromise.

Shipped

  • RFC-01 — trait distributions. Personas stop being cartoons: traits are now scalars or categorical / bounded-normal distributions, deterministic under seed, sum- and bounds-checked by the validator.
  • RFC-02 — the extension port. One sanctioned escape hatch: extensions keyed by versioned namespace (com.acme.flux/1) or x-*. Dialect fields become legal, declared, and shallow-typed — the core stays closed, and forks stop being necessary.
  • RFC-03 — module supply chain. moduleRefs: [churn-detector@^2.1] plus a flux.lock binding every versioned ref to an exact version and a content digest of the document. Reuse across teams becomes reproducible; content drift breaks the build.
  • RFC-07 — the semantic-model port. Experiment metrics bind through semanticRef to measures a Module declares on the ossie-model port — "revenue" means one governed thing per bundle, validator-enforced.
  • RFC-08 (partial) — UI hints. A generated artifact with per-kind and per-field widget metadata, enough for any tool to render authoring forms instead of hand-edited YAML. The LSP spec remains open.

Numbers

  • Regression suite: 85 checks (was 61), including per-RFC accept and reject cases and the additivity proof.
  • The example universe now exercises all five RFCs end to end — including flux.lock digest verification and semantic-measure resolution.

Next

Per the staged plan: 0.4.1 targets the Playback credibility scorecard (RFC-05) and seam version ranges + provenance (RFC-06); 0.5.0 targets the runtime enforcement contract (RFC-04) and signed bundles (RFC-09), making Level-3 Runtime certifiable.

Full field-by-field diff: Changelog.