Policy Versioning

After this lesson, the reader should understand:

• 01Bind a decision to the artifact version in force at the time.
• 02Distinguish issuance date from effective date.
• 03Handle retrospective amendment correctly.

The retrospective amendment

A rule is amended with effect from a past date. What happens to decisions already made?

With versioned artifacts the question is answerable: identify every decision bound to the superseded version whose facts fall inside the amended window, re-execute against the new version, and report the delta. Without versioning, the institution can only estimate. Retrospectivity is a policy choice; the ability to compute its consequences is an engineering property.

• Should artifacts ever be amended in place?
• How long must superseded versions remain executable?
• Who decides that a change is material?

Design a version scheme for one instrument.

1. 01Define what constitutes a material change.
2. 02Define the identity and numbering rule.
3. 03Define the retention period for superseded versions.
4. 04Describe the replay procedure.

• Temporal databases and bitemporal modelling.
• Point-in-time consolidation of legislation.
• Semantic versioning and change classification.