# Versioning **Meta-Universe Specification** **Document ID:** MU-V2-ARCH-002 **Title:** Meta-Model Architecture Standard — Versioning Strategy **Document Class:** Normative **Version:** 2.0 (Draft) **Status:** Working Draft **Normative References:** Meta-Universe Constitution (MUC), MMAS-Core **Informative References:** Naming-Conventions, MMAS-Package **Copyright:** © Orkestron.AI **License:** Apache-2.0 --- # 1. Purpose This document defines the versioning strategy for all Meta-Universe specifications, Meta-Models and related semantic artifacts. The objective is to enable continuous evolution while preserving semantic stability, interoperability and traceability. --- # 2. Scope This specification applies to: - Meta-Universe standards - Meta-Models - Bundles - Layers - Schemas - Objects - Projections - Contracts - Federation Profiles Every version SHALL be explicitly declared. --- # 3. Versioning Principles Versioning SHALL: - be explicit; - be immutable after publication; - preserve traceability; - support coexistence of multiple versions; - distinguish semantic changes from editorial changes. No published version SHALL be silently modified. --- # 4. Independent Versioning Each architectural element SHALL have its own lifecycle and version. Examples include: - Meta-Universe Specification - MUC - MMAS - MUFP - Meta-Model - Bundle - Layer - Schema - Projection Profile - Contract Updating one element SHALL NOT require changing unrelated versions. --- # 5. Semantic Versioning Specifications SHOULD follow Semantic Versioning. MAJOR : Breaking semantic changes. MINOR : New compatible capabilities. PATCH : Editorial corrections, clarifications and non-semantic improvements. Implementations MAY adopt compatible internal schemes provided semantic meaning is preserved. --- # 6. Version Identity Every versioned artifact SHALL declare: - identifier; - version; - publication date; - status; - owner; - compatibility statement. --- # 7. Semantic Fingerprint A version number declares *intent*; a **Semantic Fingerprint** declares *identity of meaning*. Each published meta-model version SHALL carry a Semantic Fingerprint computed over the **normalized semantic structure** of the model — its Objects, Properties, Relationships, Events, Contracts and Projections as defined by [MMAS-Core](MMAS-Core.md) — and NOT over the Markdown, file ordering, whitespace or other presentation. The fingerprint SHOULD be a cryptographic digest (for example `sha256`) of a canonical, deterministically serialized form of the semantic structure. Two artifacts whose meaning is identical SHALL produce the same fingerprint even if their formatting differs; any change in meaning SHALL produce a different fingerprint. A versioned artifact SHOULD declare its fingerprint alongside its version identity: ```text Version 2.1.0 Semantic Fingerprint sha256: 8D4A...F27C ``` The Semantic Fingerprint serves several purposes: - **Semantic equivalence detection** — confirm that two artifacts mean the same thing regardless of formatting or editorial differences; - **Hidden incompatibility detection** — reveal meaning changes that a version number failed to reflect (for example a PATCH release whose fingerprint changed); - **Pre-federation compatibility check** — compare fingerprints before federation to decide whether negotiation or mapping is required; - **Dependency and migration graphs** — use fingerprints as stable nodes when constructing version dependency and migration graphs across a federation. The fingerprint SHALL be reproducible: any conforming implementation given the same semantic structure SHALL compute the same value. The exact canonical serialization, the semantic/non-semantic field separation, and the hashing procedure are defined normatively in [MMAS-Interchange (MUIF)](MMAS-Interchange.md), with a verified worked example and a reference implementation. The Semantic Fingerprint pairs with the [Canonical Semantic Name](Naming-Conventions.md) to identify a concept both by stable name and by stable meaning, and it is one of the metadata fields carried by a [Semantic Distribution Package](MMAS-Package.md). --- # 8. Compatibility Every published version SHALL state its compatibility with previous versions. Compatibility SHOULD be classified as: - Fully Compatible - Backward Compatible - Forward Compatible - Requires Migration - Breaking --- # 9. Coexistence Multiple versions MAY coexist simultaneously. Implementations SHOULD support explicit version negotiation whenever federation involves different versions. --- # 10. Deprecation Artifacts SHOULD be deprecated before removal. A deprecation notice SHALL identify: - deprecated artifact; - replacement; - deprecation version; - planned removal version. --- # 11. Migration Breaking changes SHALL include migration guidance. Migration documentation SHOULD describe: - affected concepts; - semantic differences; - required transformations; - compatibility strategy; - examples. --- # 12. Imported Standards Imported semantic standards SHALL preserve their original version identifiers. Local extensions SHALL maintain an explicit mapping between imported versions and local extensions. --- # 13. Historical Preservation Historical versions SHALL remain identifiable and reproducible. Previous versions SHOULD remain publicly available whenever possible. Historical versions SHALL NOT be rewritten. --- # 14. Version Negotiation Federated universes SHOULD declare supported versions during capability discovery. If incompatible versions are detected, implementations SHOULD: - negotiate a compatible version; - apply semantic mappings; - request migration; - or reject federation. --- # 15. Architectural Invariants Version changes SHALL NEVER invalidate: - global identity; - ownership; - provenance; - traceability; - constitutional compliance. These invariants are governed by MUC. --- # 16. Future Directions The Semantic Fingerprint enables a fingerprint-driven view of evolution that future work may standardize as a **Semantic Migration Standard (SMS)**. Such a standard would treat fingerprints as the canonical nodes of a federation-wide version dependency and migration graph, define how migration transformations are attached to fingerprint pairs, and specify how negotiating universes select a migration path automatically. The fingerprint computation itself may also warrant a small companion profile that fixes the normalization and serialization procedure so that every implementation produces byte-identical digests. --- # Final Statement Versioning in Meta-Universe exists to preserve semantic continuity. Evolution is encouraged, but every change must remain explicit, traceable, compatible whenever practical and understandable by both humans and AI systems.