Skip to main content
Suspec
manual page/ Reference

Drift

sourceSource: suspec/docs/reference/drift.mdModified: 2026-06-26
Sections
7
Format
Markdown
Order
26 / 156

Drift is a mismatch between intent and evidence.

It happens when a requirement, code path, or verify command changes after a prior Pass.

Drift triggers

Old evidence becomes stale when:

  • requirement text changes
  • non-goals change
  • Verify with: changes
  • exercised code changes
  • the command target changes
  • the evidence path no longer exists

Result

Use Stale for a prior Pass that needs re-checking.

Do not keep the old Pass silently.

Resolution

Pick one:

  • re-run the verification
  • amend the requirement
  • fix the code

Do not let code redefine intent without an amendment.

Amending a living spec

A spec is a living organism: amend the original rather than write a new one (ADR-0108).

  • Review on touch. When a change touches a spec's evidence path, amend the spec in the same change — the moment its code moves is the moment to fix its intent. Amendment is change-triggered; there is no scheduled spec audit.
  • Amend vs supersede. Amend an AC's text in place as the feature evolves (it keeps its id); mark an AC superseded in place when it is retired; mint a new spec (and set the old one's superseded_by) only when a whole feature is replaced.
  • Status. A spec moves ready → active once it is in use and being amended; superseded only on whole-feature replacement. This is the spec's lifecycle maturity (draft → ready → active → superseded), not its workflow position (in-progress / in-review / done) — that lives on the board and the task, never in the spec's status.

Evidence path

The evidence path is what the check actually exercised.

Examples:

  • test file
  • integration route
  • API contract
  • migration script
  • browser path

If later work edits that path, review the old evidence for staleness.

Scope

Only declared drift needs action.

Do not reopen unrelated old work unless the current change touches its evidence path or requirement.

Starter kit: Set up a workspace