Compare
Fix the approved baseline and proposed release. Record the versions, purpose, users, data, model, integrations, oversight and controls.
What DELTA does
A change log tells you what changed. DELTA tells you what follows.
DELTA turns a proposed system change into a bounded release-control decision.
In one sentence
Compare the approved version with the proposed release, then reopen only the work the change affects.
DELTA asks one operational question:
Does this change disturb the purpose, capability, affected people, actor responsibilities, evidence or controls that supported the existing approval?
It does not ask whether the system looks broadly similar or keeps the same product name. It fixes two versions and tests the transition between them.
Use DELTA when
The system has changed, but the consequences remain unclear.
New model or model versionNew provider or supplierFine-tuning or retrieval addedNew dataset or data sourceNew inference or scoreNew market or user groupNew intended purposeMore consequential decision roleNew tool or external actionReduced human oversightExpanded access or onward transferControl, incident or audit failure
The four moves
From engineering fact to governance decision.
Trace
Identify how the change alters capability, consequences, actors, evidence, access and the operating environment.
Reopen
Preserve valid work. Name the classifications, assessments, tests, notices or approvals that require attention.
Decide
Record the release route, reasons, conditions, owners, evidence gaps and future review events.
What it produces
Not a score. A working governance record.
DELTA produces a reasoned outcome and the evidence trail beneath it. A senior decision-maker can read the first page. Legal, engineering, compliance and audit teams can inspect the detailed record.
Worked example
From CV summary to automated rejection.
Approved baseline
The system summarises applications. A recruiter reads the underlying material and decides what to do.
Proposed release
The revised system ranks applicants, predicts retention risk, rejects people below a threshold and sends an email unless a recruiter intervenes.
What changed
Purpose, decision consequence, model, data, inference, population, autonomy, supplier, tool access and oversight.
DELTA route
Deployment hold. The revision creates unresolved red-line concerns and external action authority without completed validation, assessment and oversight evidence.
The boundary
What DELTA does not do.
It does not replace specialist assessments.
DELTA may identify the need to revisit an AI classification, DPIA, FRIA, conformity assessment, security review, validation exercise, consumer-fairness review or human-oversight analysis. It does not complete those exercises inside one generic form.
It does not certify the release.
The organisation’s authorised decision-maker must evaluate the evidence and accept, condition, defer or reject the release. DELTA records that decision; it does not assume it.
It does not monitor production.
DELTA assesses a defined transition at a defined time. Continuous monitoring, incident detection, model evaluation and runtime controls require separate systems.
It does not reward optimistic answers.
“Not sure” remains a substantive answer. The outcome logic treats unresolved material issues as evidence gaps or escalation triggers rather than silently converting them into compliance.
Two minutes becomes a record
See the method with fictional facts.
The public demonstration opens fully populated. Change the answers, inspect the reasons and print a watermarked sample report.