** Version: 0.1 (Draft)\ Status:** Proposed — Non-Canonical
1. Purpose ————--
This specification defines the rules by which a GEOS-certified Data Pipeline may evolve over time without compromising auditability, comparability, or finance-grade reliability.
It ensures that certified Data Pipelines can change in controlled, explicit ways while preserving the integrity of Outcome Signals derived from them across reporting periods.
2. Scope ————
This specification applies to:
Any Data Pipeline seeking initial GEOS certification, and
Any previously certified Data Pipeline undergoing modification.
This document governs how a Data Pipeline may change.\ It does not define certification criteria (GEOS-DP-002, entry requirements (GEOS-DP-004, exit requirements (GEOS-DP-005, or traceability mechanics (GEOS-DP-006.
3. Version Identity ———————--
Each certified Data Pipeline MUST have a unique Pipeline Version Identifier.
A Pipeline Version Identifier MUST:
Be immutable once issued
Be explicitly declared in all certification artifacts
Be referenced by all downstream artifacts produced by that pipeline version
A change to any normative aspect of a Data Pipeline MUST result in a new Pipeline Version Identifier.
4. Classes of Change ————————
Changes to a Data Pipeline are classified as follows.
Non-normative changes do not affect the meaning, structure, or auditability of pipeline outputs.
Examples include:
Documentation clarifications
Non-functional implementation optimizations
Operational tooling changes that do not alter declared behavior
Non-normative changes:
MUST be documented
MUST NOT require re-certification
MUST NOT change the Pipeline Version Identifier
Normative changes alter the semantics, structure, or evidentiary properties of the pipeline.
Examples include changes to:
Entry data interpretation
Transformation logic affecting outcome construction
Aggregation rules
Output artifact structure
Traceability guarantees
Normative changes:
MUST result in a new Pipeline Version Identifier
MUST trigger a new certification assessment
MUST preserve access to prior certified versions for audit purposes
5. Backward Compatibility —————————--
A Data Pipeline MAY declare backward compatibility with one or more prior versions.
If backward compatibility is declared, the pipeline MUST:
Explicitly state the compatibility scope
Demonstrate that outputs are equivalent within declared tolerances
Preserve traceability across version boundaries
Backward compatibility claims are subject to certification review.
6. Version Coexistence ————————--
Multiple certified versions of the same Data Pipeline MAY coexist.
When versions coexist:
Each version MUST be independently identifiable
Outputs MUST be clearly attributable to a specific version
No version may overwrite or obscure artifacts produced by another version
This enables longitudinal analysis without retroactive reinterpretation.
7. Deprecation ——————
A Data Pipeline version MAY be deprecated.
Deprecation:
MUST be explicitly declared
MUST NOT invalidate previously produced artifacts
MUST include a clear deprecation date
Deprecation does not imply decertification of historical outputs.
8. Prohibited Evolution Patterns ————————————
A Data Pipeline MUST NOT:
Change normative behavior without version increment
Retroactively alter previously emitted artifacts
Reinterpret historical data under a new version
Implicitly replace one version with another
Silent evolution is strictly prohibited.
9. Relationship to Certification ————————————
Certification applies to a specific Pipeline Version Identifier.
A certification decision:
Applies only to the assessed version
Does not automatically extend to future versions
Does not imply endorsement of evolution direction
Each version stands on its own certification evidence.
10. Canonical Principle Alignment ————————————-
This specification enforces the GEOS Canon principle:
Artifacts must declare their dependencies, but never their dependents.
A Data Pipeline version declares:
It MUST NOT declare:
Which Outcome Signal Portfolios rely on it
How downstream actors choose to use its outputs
END of \"GEOS-DP-008 — Data Pipeline Versioning & Evolutio Rules\"