Planning Technical Migrations | Phased Approach Guide
Plan technical migrations in phases: preparation, POC, staged rollout, cutover, cleanup. Track parallel workstreams and rollbacks with GitScrum.
14 min read
Technical migrations—database upgrades, framework changes, infrastructure moves, API version transitions—are complex undertakings that affect entire codebases and can derail normal development for months if poorly managed. GitScrum's project organization, milestone tracking, and workload visibility help teams plan migrations in phases, track parallel efforts, identify risks early, and maintain delivery velocity throughout the migration process.
Migration Planning
Assessment Phase
BEFORE YOU START:
┌─────────────────────────────────────────────────────────────┐
│ MIGRATION READINESS ASSESSMENT │
├─────────────────────────────────────────────────────────────┤
│ │
│ SCOPE DEFINITION: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ What's changing: ││
│ │ • Current state: [e.g., React 17, MongoDB 4.4] ││
│ │ • Target state: [e.g., React 18, MongoDB 6.0] ││
│ │ • Components affected: [list services/modules] ││
│ │ ││
│ │ Document in NoteVault: ││
│ │ "Migration: [Name] - Scope Document" ││
│ │ ││
│ │ Include: ││
│ │ • Why migrate? (end of support, features, performance) ││
│ │ • What if we don't? (risks of staying) ││
│ │ • Success criteria: How do we know we're done? ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ IMPACT MAPPING: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ For each affected area: ││
│ │ ││
│ │ Component │ Impact │ Effort │ Dependencies ││
│ │ ────────────────┼────────┼────────┼────────────── ││
│ │ User Service │ High │ L │ Auth Service ││
│ │ Payment Module │ High │ XL │ Stripe API ││
│ │ Reports Engine │ Medium │ M │ Analytics DB ││
│ │ Admin Panel │ Low │ S │ User Service ││
│ │ ││
│ │ Create as table in NoteVault or spreadsheet linked ││
│ │ from task description ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ RISK IDENTIFICATION: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Known risks: ││
│ │ ││
│ │ Risk │ Likelihood │ Impact │ Mitigation ││
│ │ ───────────────────┼────────────┼────────┼────────── ││
│ │ Data corruption │ Low │ High │ Full backup ││
│ │ Extended downtime │ Medium │ High │ Blue-green ││
│ │ Performance drop │ Medium │ Medium │ Load testing ││
│ │ Feature regression │ High │ Medium │ Test suite ││
│ │ Team unavailable │ Low │ High │ Document all ││
│ │ ││
│ │ Track risks as labeled tasks: label "risk/migration" ││
│ └─────────────────────────────────────────────────────────┘│
│ │
└─────────────────────────────────────────────────────────────┘
Phased Approach
BREAKING DOWN MIGRATION:
┌─────────────────────────────────────────────────────────────┐
│ MIGRATION PHASES │
├─────────────────────────────────────────────────────────────┤
│ │
│ PHASE 0: PREPARATION (1-2 sprints) │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Tasks: ││
│ │ ☐ Complete impact assessment ││
│ │ ☐ Create migration documentation ││
│ │ ☐ Set up parallel environment ││
│ │ ☐ Expand test coverage for affected areas ││
│ │ ☐ Train team on new technology ││
│ │ ☐ Define rollback procedures ││
│ │ ││
│ │ Exit criteria: Team confident to proceed ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ PHASE 1: PROOF OF CONCEPT (1 sprint) │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Tasks: ││
│ │ ☐ Migrate smallest, lowest-risk component ││
│ │ ☐ Validate approach works ││
│ │ ☐ Identify unexpected issues ││
│ │ ☐ Refine effort estimates ││
│ │ ☐ Document patterns and antipatterns found ││
│ │ ││
│ │ Exit criteria: One component migrated, issues known ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ PHASE 2: STAGED ROLLOUT (2-4 sprints) │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Approach: ││
│ │ • Migrate in dependency order (leaves first) ││
│ │ • Each component: migrate → test → deploy → monitor ││
│ │ • Pause between components for stabilization ││
│ │ ││
│ │ Priority order: ││
│ │ 1. Low-risk, few dependencies ││
│ │ 2. Medium-risk, tested patterns ││
│ │ 3. High-risk, critical path (most preparation) ││
│ │ ││
│ │ Exit criteria: All components migrated except cutover ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ PHASE 3: CUTOVER (1 sprint or weekend) │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Tasks: ││
│ │ ☐ Final data migration ││
│ │ ☐ DNS/routing changes ││
│ │ ☐ Remove old system access ││
│ │ ☐ Intensive monitoring period ││
│ │ ☐ On-call rotation for issues ││
│ │ ││
│ │ Exit criteria: New system handling all traffic ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ PHASE 4: CLEANUP (1-2 sprints) │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Tasks: ││
│ │ ☐ Remove compatibility layers ││
│ │ ☐ Delete old code/infrastructure ││
│ │ ☐ Update all documentation ││
│ │ ☐ Close migration project ││
│ │ ☐ Retrospective: What did we learn? ││
│ │ ││
│ │ Exit criteria: No traces of old system remain ││
│ └─────────────────────────────────────────────────────────┘│
│ │
└─────────────────────────────────────────────────────────────┘
Tracking in GitScrum
Board Organization
MIGRATION PROJECT STRUCTURE:
┌─────────────────────────────────────────────────────────────┐
│ ORGANIZING MIGRATION WORK │
├─────────────────────────────────────────────────────────────┤
│ │
│ OPTION 1: DEDICATED MIGRATION BOARD │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Board: "React 18 Migration" ││
│ │ ││
│ │ Columns: ││
│ │ [Backlog] → [This Phase] → [In Progress] → ││
│ │ [Testing] → [Deployed] → [Verified] ││
│ │ ││
│ │ Swimlanes (by phase): ││
│ │ ───────────────────────────────────── ││
│ │ PHASE 0: Preparation ││
│ │ PHASE 1: POC ││
│ │ PHASE 2: Staged Rollout ││
│ │ PHASE 3: Cutover ││
│ │ PHASE 4: Cleanup ││
│ │ ││
│ │ Best for: Large migrations with dedicated team ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ OPTION 2: LABELS ON MAIN BOARD │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Use labels to identify migration work: ││
│ │ ││
│ │ 🔴 migration/react-18 ││
│ │ 🟡 migration/phase-1 ││
│ │ 🟢 migration/complete ││
│ │ ││
│ │ Filter board by migration label to see: ││
│ │ • All migration tasks ││
│ │ • Progress by phase ││
│ │ ││
│ │ Best for: Smaller migrations mixed with regular work ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ TASK STRUCTURE: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Epic: "React 18 Migration" ││
│ │ ├── User Service Migration ││
│ │ │ ├── Update dependencies ││
│ │ │ ├── Fix breaking changes ││
│ │ │ ├── Update tests ││
│ │ │ └── Deploy and verify ││
│ │ ├── Payment Module Migration ││
│ │ │ ├── ...subtasks... ││
│ │ └── Reports Engine Migration ││
│ │ └── ...subtasks... ││
│ │ ││
│ │ Each component = one parent task with subtasks ││
│ └─────────────────────────────────────────────────────────┘│
│ │
└─────────────────────────────────────────────────────────────┘
Progress Tracking
MEASURING MIGRATION PROGRESS:
┌─────────────────────────────────────────────────────────────┐
│ VISIBILITY INTO MIGRATION STATUS │
├─────────────────────────────────────────────────────────────┤
│ │
│ COMPONENT TRACKING: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Migration Status Dashboard (in NoteVault): ││
│ │ ││
│ │ Component │ Status │ Owner │ Notes ││
│ │ ─────────────────┼─────────────┼──────────┼────── ││
│ │ User Service │ ✅ Complete │ @maria │ Deployed ││
│ │ Auth Service │ 🔄 Testing │ @carlos │ In staging ││
│ │ Payment Module │ 🚧 In Prog │ @ana │ 60% done ││
│ │ Reports Engine │ ⏳ Queued │ TBD │ Phase 2 ││
│ │ Admin Panel │ ⏳ Queued │ TBD │ Phase 2 ││
│ │ ││
│ │ Update weekly, share in Discussions ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ METRICS TO TRACK: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Progress: ││
│ │ • Components migrated: 2/8 (25%) ││
│ │ • Lines of code migrated: 12,000/50,000 (24%) ││
│ │ • Tests passing: 847/900 (94%) ││
│ │ ││
│ │ Velocity: ││
│ │ • Avg days per component: 5 ││
│ │ • Components this sprint: 2 ││
│ │ • Projected completion: Sprint 47 ││
│ │ ││
│ │ Issues: ││
│ │ • Blockers found: 3 ││
│ │ • Blockers resolved: 2 ││
│ │ • Rollbacks needed: 0 ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ WEEKLY UPDATE FORMAT: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Post in Discussions weekly: ││
│ │ ││
│ │ "Migration Update - Week 3" ││
│ │ ││
│ │ ✅ Completed this week: ││
│ │ • User Service migrated and deployed ││
│ │ • Auth Service testing complete ││
│ │ ││
│ │ 🚧 In progress: ││
│ │ • Payment Module - addressing Stripe API changes ││
│ │ ││
│ │ ⚠️ Risks/blockers: ││
│ │ • Discovered breaking change in date handling ││
│ │ • Mitigation: [link to investigation task] ││
│ │ ││
│ │ 📅 Next week: ││
│ │ • Complete Payment Module ││
│ │ • Start Reports Engine ││
│ └─────────────────────────────────────────────────────────┘│
│ │
└─────────────────────────────────────────────────────────────┘
Parallel Workstreams
Migration vs Features
MAINTAINING DELIVERY:
┌─────────────────────────────────────────────────────────────┐
│ BALANCING MIGRATION WITH REGULAR WORK │
├─────────────────────────────────────────────────────────────┤
│ │
│ ALLOCATION MODELS: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Option A: Dedicated Migration Team ││
│ │ ──────────────────────────────── ││
│ │ • 2-3 developers 100% on migration ││
│ │ • Rest of team continues features ││
│ │ • Clear handoffs when components done ││
│ │ ││
│ │ Pros: Fast migration, clear focus ││
│ │ Cons: Knowledge silos, "us vs them" ││
│ │ ││
│ │ ─────────────────────────────────────────────────────── ││
│ │ ││
│ │ Option B: Rotation ││
│ │ ──────────────────── ││
│ │ • Each sprint, 1-2 devs rotate onto migration ││
│ │ • Everyone touches migration eventually ││
│ │ • Context switching is expected ││
│ │ ││
│ │ Pros: Knowledge spreads, no silos ││
│ │ Cons: Slower, more context switching ││
│ │ ││
│ │ ─────────────────────────────────────────────────────── ││
│ │ ││
│ │ Option C: Percentage Allocation ││
│ │ ───────────────────────────────── ││
│ │ • Every developer: 30% migration, 70% features ││
│ │ • Migration work interleaved with regular work ││
│ │ ││
│ │ Pros: Flexible, everyone learns ││
│ │ Cons: Slow, high context switching cost ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ SPRINT PLANNING FOR PARALLEL WORK: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Sprint capacity: 80 points ││
│ │ ││
│ │ Split: ││
│ │ • Migration: 30 points (37%) ││
│ │ • Features: 40 points (50%) ││
│ │ • Bugs: 10 points (13%) ││
│ │ ││
│ │ Use labels to visualize split in sprint view ││
│ │ Adjust percentages based on phase urgency ││
│ └─────────────────────────────────────────────────────────┘│
│ │
└─────────────────────────────────────────────────────────────┘
Coordination
KEEPING WORKSTREAMS ALIGNED:
┌─────────────────────────────────────────────────────────────┐
│ COMMUNICATION PATTERNS │
├─────────────────────────────────────────────────────────────┤
│ │
│ DAILY STANDUP: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Include migration check-in: ││
│ │ ││
│ │ Regular standup: ││
│ │ • What I did / What I'll do / Blockers ││
│ │ ││
│ │ Add for migration period: ││
│ │ • "Migration status: [component] at [%]" ││
│ │ • "Cross-team dependency: Need X from feature work" ││
│ │ ││
│ │ Or use Team Standup for async updates with ││
│ │ migration-specific questions ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ DEPENDENCY MANAGEMENT: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ When feature work depends on migration: ││
│ │ ││
│ │ Feature Task: "Add user preferences" ││
│ │ Blocked by: "User Service Migration" [linked] ││
│ │ Status: Waiting ││
│ │ ││
│ │ When migration depends on feature work: ││
│ │ ││
│ │ Migration Task: "Migrate Reports Engine" ││
│ │ Depends on: "New analytics schema" [linked] ││
│ │ Status: Ready when dependency complete ││
│ │ ││
│ │ Use task linking to track cross-workstream deps ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ CONFLICT RESOLUTION: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ When migration and features conflict: ││
│ │ ││
│ │ Scenario: "Should we add feature X to old or new ││
│ │ system?" ││
│ │ ││
│ │ Decision tree: ││
│ │ • If component migrating < 2 weeks: Wait for new ││
│ │ • If component migrating > 2 weeks: Build in old, ││
│ │ then migrate ││
│ │ • If urgent: Build in both (accept double work) ││
│ │ ││
│ │ Document decision in task comments ││
│ └─────────────────────────────────────────────────────────┘│
│ │
└─────────────────────────────────────────────────────────────┘
Risk Management
Rollback Planning
PREPARING FOR FAILURE:
┌─────────────────────────────────────────────────────────────┐
│ ROLLBACK STRATEGY │
├─────────────────────────────────────────────────────────────┤
│ │
│ BEFORE EACH COMPONENT MIGRATION: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Rollback checklist: ││
│ │ ││
│ │ ☐ Database backup taken ││
│ │ ☐ Old version deployable ││
│ │ ☐ Rollback procedure documented ││
│ │ ☐ Rollback tested in staging ││
│ │ ☐ Rollback criteria defined ││
│ │ ☐ Rollback owner assigned ││
│ │ ││
│ │ Create as subtask checklist in migration task ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ ROLLBACK CRITERIA: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Define in advance when to rollback: ││
│ │ ││
│ │ Automatic rollback if: ││
│ │ • Error rate > 5% (was < 0.5%) ││
│ │ • Response time > 2s (was < 500ms) ││
│ │ • Critical functionality broken ││
│ │ ││
│ │ Manual decision if: ││
│ │ • Minor issues fixable in < 1 hour ││
│ │ • Degraded but functional ││
│ │ • Workaround available ││
│ │ ││
│ │ Document in NoteVault: "Migration Runbook" ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ ROLLBACK PROCEDURE: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Step-by-step (example): ││
│ │ ││
│ │ 1. Announce in #incidents: "Rolling back [component]" ││
│ │ 2. Run: ./scripts/rollback-user-service.sh ││
│ │ 3. Verify: Check dashboard for error rates ││
│ │ 4. Confirm: Test critical user flows ││
│ │ 5. Communicate: Update #incidents with status ││
│ │ 6. Investigate: Create post-rollback investigation ││
│ │ task ││
│ │ ││
│ │ Target: Rollback complete in < 15 minutes ││
│ └─────────────────────────────────────────────────────────┘│
│ │
└─────────────────────────────────────────────────────────────┘
Migration Retrospective
LEARNING FROM MIGRATION:
┌─────────────────────────────────────────────────────────────┐
│ POST-MIGRATION REVIEW │
├─────────────────────────────────────────────────────────────┤
│ │
│ RETROSPECTIVE QUESTIONS: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Planning: ││
│ │ • Was our scope assessment accurate? ││
│ │ • Did we identify the right risks? ││
│ │ • How far off were our estimates? ││
│ │ ││
│ │ Execution: ││
│ │ • What surprised us? ││
│ │ • Which phase was hardest? ││
│ │ • Did our phasing approach work? ││
│ │ ││
│ │ Team: ││
│ │ • How was the workload balance? ││
│ │ • Did knowledge transfer succeed? ││
│ │ • What would we tell past-us? ││
│ │ ││
│ │ Process: ││
│ │ • Did our tracking approach work? ││
│ │ • What communication gaps existed? ││
│ │ • What would we do differently? ││
│ └─────────────────────────────────────────────────────────┘│
│ │
│ DOCUMENT LEARNINGS: │
│ ┌─────────────────────────────────────────────────────────┐│
│ │ Save in NoteVault for future migrations: ││
│ │ ││
│ │ "Migration Retrospective: React 18 Upgrade" ││
│ │ ││
│ │ Sections: ││
│ │ • Summary: What we migrated, timeline, outcome ││
│ │ • What went well: Patterns to repeat ││
│ │ • What went poorly: Mistakes to avoid ││
│ │ • Unexpected challenges: Future warnings ││
│ │ • Recommendations: Advice for next migration ││
│ │ ││
│ │ Link from migration epic as final artifact ││
│ └─────────────────────────────────────────────────────────┘│
│ │
└─────────────────────────────────────────────────────────────┘