Monolith to Microservices

Strategies for gradual migration.

  • Strangler Fig: Gradually replace monolith
  • Extract Service: Pull out one service at a time
  • Anti-Corruption Layer: Protect new code from old

Migration Patterns

Database decomposition, data synchronization, dual writes.

Dual Write Pattern
# Write to both old and new systems
old_db.save(user)
new_service.create_user(user)

Large-Scale Migration

Organizational changes, team structure, and cultural shifts.

Amazon Migration

Took 5+ years to fully migrate to microservices