Function as a Service (FaaS)

  • Definition: Execution model where provider dynamically manages resources
  • Key characteristics:
    • Event-driven architecture
    • Ephemeral logic (functions) created only when needed
    • Pay-per-execution (“no idle resources”)
    • Stateless execution
    • Time-limited (typically 5-15 minutes maximum)
  • Components:
    • Function execution environment
    • API Gateway for HTTP requests
    • Event Sources (message queues, storage events, etc.)
    • State Management (external databases, caches)
  • Examples:
    • AWS Lambda
    • Azure Functions
    • Google Cloud Run
    • Cloudflare Workers
  • Benefits:
    • Lower costs (precise usage-based billing)
    • No servers to manage (reduced complexity)
    • Enhanced scalability
    • Faster deployment times
  • Challenges:
    • Cold start latency impacts
    • Vendor lock-in through platform services
    • Complex state management
    • Memory and time constraints