Serverless Callbacks Migration

Proposal to migrate callbacks functionality to serverless architecture

Summary

Proposal to migrate callbacks functionality to a serverless architecture.

Rationale

[To be filled in - reasons for migrating to serverless]

Key benefits expected:

  • Improved scalability for callback processing
  • Reduced operational overhead
  • Cost optimization through pay-per-use model
  • Better handling of variable callback volumes
  • Enhanced reliability and retry mechanisms

Affected Applications

Impact

Services Affected

  • Callback handling services
  • [List additional services and dependencies]

Technical Considerations

  • Webhook/callback endpoint compatibility
  • Event-driven architecture implementation
  • Asynchronous processing requirements
  • Retry and failure handling
  • Message queue integration
  • Timeout and execution limits

Data Considerations

  • Callback data storage and logging
  • Event sourcing patterns
  • Audit trail requirements
  • Dead letter queue handling

Implementation Plan

Phase 1: Assessment & Design

  • Document current callback workflows
  • Identify all callback sources and consumers
  • Design event-driven serverless architecture
  • Evaluate messaging/queue services (SQS, EventBridge, etc.)
  • Define retry and error handling strategy
  • Assess monitoring requirements
  • Create proof of concept

Phase 2: Development

  • Set up serverless infrastructure
  • Implement event handlers and processors
  • Configure API Gateway for webhook endpoints
  • Set up message queues and event routing
  • Implement retry logic and dead letter queues
  • Set up monitoring, logging, and alerting
  • Create comprehensive test suite including failure scenarios

Phase 3: Migration

  • Deploy to staging environment
  • Integration testing with callback sources
  • Load and stress testing
  • Failure scenario testing
  • Latency and performance validation
  • Security review
  • Create rollback procedures

Phase 4: Cutover

  • Deploy to production
  • Gradual traffic migration
  • Monitor callback processing rates and success
  • Update webhook endpoint configurations
  • Validate end-to-end callback flows
  • Decommission old infrastructure
  • Archive legacy documentation

Risks & Mitigation

RiskImpactMitigation
Callback delivery failuresHighImplement robust retry mechanisms and dead letter queues
Duplicate callback processingMediumImplement idempotency keys and deduplication
Cold start latencyMediumUse provisioned concurrency for critical callbacks
Message loss during migrationHighParallel processing with validation before cutover
Timeout issues for long-running callbacksMediumDesign async processing patterns, evaluate timeout limits
Integration breakageHighExtensive testing with all callback sources
Monitoring gapsMediumComprehensive logging and alerting setup

Timeline

[To be determined]

Status

Current Status: Draft

History:

  • 2025-12-22: Proposal created
Last modified February 5, 2026: Adds proposal summary (2c393ca)