---
phase: 03-generate-node-refactor
plan: 03
subsystem: compatibility
tags: [migration, backward-compatibility, legacy-workflows, multi-provider]

# Dependency graph
requires:
  - phase: 03-01
    provides: GenerateImageNode with SelectedModel type
  - phase: 03-02
    provides: Multi-provider dispatch in /api/generate route
provides:
  - Workflow migration logic for legacy nanoBanana nodes
  - Multi-provider execution with API key headers in workflowStore
  - Legacy data handling in GenerateImageNode UI
affects: [04-model-search-dialog]

# Tech tracking
tech-stack:
  added: []
  patterns:
    - Workflow migration on load in loadWorkflow()
    - UI-side migration effect for runtime compatibility

key-files:
  created: []
  modified:
    - src/store/workflowStore.ts
    - src/components/nodes/GenerateImageNode.tsx

key-decisions:
  - "Dual migration: loadWorkflow migrates data, UI effect ensures runtime compatibility"
  - "API key headers passed from providerSettings state in executeWorkflow/regenerateNode"
  - "selectedModel included in request payload for provider routing"

patterns-established:
  - "Migration pattern: check for old data format, derive new format, update node"
  - "Provider-agnostic logging: use provider variable in log messages"

issues-created: []

# Metrics
duration: 3 min
completed: 2026-01-09
---

# Phase 3 Plan 3: Backward Compatibility Summary

**Workflow migration logic and multi-provider execution in workflowStore ensuring legacy Gemini workflows load and execute unchanged**

## Performance

- **Duration:** 3 min
- **Started:** 2026-01-09T07:43:18Z
- **Completed:** 2026-01-09T07:46:38Z
- **Tasks:** 3
- **Files modified:** 2

## Accomplishments
- Workflow migration on load: legacy nanoBanana nodes without selectedModel auto-populated
- Multi-provider execution: API key headers and selectedModel passed in requests
- UI-side migration: GenerateImageNode derives selectedModel on mount for runtime compatibility

## Task Commits

Each task was committed atomically:

1. **Task 1: Add workflow migration logic** - `2811e62` (feat)
2. **Task 2: Update executeWorkflow for multi-provider** - `da326c9` (feat)
3. **Task 3: Handle legacy data in UI** - `88b8962` (feat)

**Plan metadata:** `0e1f163` (docs: complete plan)

## Files Created/Modified
- `src/store/workflowStore.ts` - Migration in loadWorkflow, API key headers in executeWorkflow/regenerateNode
- `src/components/nodes/GenerateImageNode.tsx` - useEffect for UI-side migration

## Decisions Made
- Dual migration approach: server-side on workflow load + client-side for runtime
- API key headers (X-Replicate-API-Key, X-Fal-API-Key) for external providers
- selectedModel included in request body for provider dispatch

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered

None

## Next Phase Readiness
- Phase 3 (Generate Node Refactor) complete
- All legacy workflows load with auto-populated selectedModel
- Multi-provider execution working for Gemini, Replicate, and fal.ai
- Ready for Phase 4: Model Search Dialog

---
*Phase: 03-generate-node-refactor*
*Completed: 2026-01-09*