Phase E — Parity verification and cutover

Prove the Avalonia line is the maintenance trunk, document gaps, then freeze or delete legacy only with evidence.

Read acceptance to build repository-specific scenarios, legacy diff to record evidence, and cutover checklist before freezing or deleting legacy code.

Workflow

1. Capability matrix

| Feature | New status | Diff / gap | Impact | Decision (fix/defer/retire) |

Populate the matrix from Phase A. Cover every user command, state transition, external effect, failure/recovery path, accessibility contract, supported environment, and deployment path that the product actually has.

2. Automated verification

Run solution and layer-focused tests; record commands. Sequential multi-project runs if needed.

For large multi-module parity audits, use independent read-only sub-agents per module so conclusions do not pollute one context.

3. Acceptance checklist

Run the Phase A acceptance scenarios against both implementations where possible. Include startup/lifecycle, primary and secondary workflows, invalid input, cancellation, dependency failure, stale-state prevention, accessibility, and recovery.

4. Modernization pass

If still WinForms-shaped (Refresh, no composition root), file and fix high-severity items.

5. Packaging

For each supported target, verify build, publish, install/launch, upgrade or replacement policy, runtime dependencies, assets, licenses, and rollback/recovery expectations.

6. Cutover stages

1. Trunk switch — all new work on Avalonia/src
2. Legacy freeze — reference only
3. Gap burn-down or waivers
4. Physical delete only after checklist

“Main path works” is not enough when any required capability or environment remains unverified.

7. Spec verification method

Per capability: implementation status plus automated/manual evidence. Do not mark done when only empty entry points exist. Treat missing untrusted-input bounds, durable persistence, or supported-environment smoke evidence as cutover blockers unless explicitly waived.

Deliverables

• Parity/diff report with decisions
• Test results summary
• Acceptance notes
• Packaging note
• Cutover checklist or dated deferrals

After E

First migration done ≠ product complete. Continue with:

• wfa-post-port-evolve for product upgrades
• wfa-harden-decompose for structure/security debt