EDI → API Migration Checklist (45+ Trading Partners)

Quality Gate: Integration Inventory (Your Baseline)

• Partner list validated (active, dormant, seasonal, high-risk/high-volume).
• Transaction catalog built (docs/messages per partner, versions, SLAs, dependencies).
• Failure modes documented (most common errors, manual workarounds, reconciliation gaps).
• Business criticality tiering defined (Tier 1 partners get the strongest migration support).

Quality Gate: Phased Cutover (Minimize Risk)

• Wave plan defined (pilot partners → mid-volume → Tier 1).
• Dual-run strategy defined (EDI + API in parallel where feasible; compare outcomes).
• Rollback posture defined (what triggers rollback; how fast it can happen).
• Partner comms plan published (timelines, testing windows, cutover dates, support channels).
• Decommission plan defined (when legacy EDI paths are retired and how exceptions are handled).

Guardrail KPIs

• Transaction success rate (by message type + by partner tier)
• Mean time to detect / resolve (MTTD/MTTR)
• Duplicate / out-of-sequence events
• Manual intervention rate
• Partner onboarding cycle time
• Chargebacks / compliance failures tied to data issues
• Latency (end-to-end) for critical flows

Key Risk Callouts

Stabilization + Hypercare Expectations

• Integration command center live (single intake, severity model, partner triage queue).
• Dedicated Tier 1 support coverage (extended hours during cutover weeks).
• Daily cutover war room (success rate first, then incidents, then change approvals).
• Hypercare exit criteria: stability for 10 business days post-wave, no repeat Sev-1s.
• Knowledge base enforced (known errors, partner quirks, runbooks, mapping clarifications).

Long-Term Maintenance

• API versioning governance (deprecation timelines, partner comms, backward compatibility).
• Partner scorecards (failure rate, response time, compliance issues).
• Quarterly integration health review (top errors, mapping drift, performance bottlenecks).
• Legacy retirement policy enforced (reduce complexity; don't keep everything forever).