Serverless Computing: Pros, Cons, and Patterns

Serverless computing lets you run code without managing servers. You write small functions and the platform handles hosting, scaling, and fault tolerance. You pay only for the compute time you use. This model can speed up development and reduce operations, but it also comes with tradeoffs that affect design and cost.

Pros of serverless

  • Quick scaling and no server maintenance
  • Pay-as-you-go pricing and cost visibility
  • Faster time to market and lighter deployment
  • Built-in reliability, uptime, and automatic updates
  • Smaller teams can ship features faster and focus on product value

Cons to consider

  • Cold starts and occasional latency for individual requests
  • Vendor lock-in and limited control over environment
  • Debugging, local testing, and reproducing issues can be harder
  • Runtime, memory, and regional limits constrain some tasks
  • Security, compliance, and data residency require careful planning
  • Not ideal for long-running, resource-heavy jobs

Patterns you can use

  • Event-driven functions: respond to storage, queues, and API calls
  • API backends: stateless functions behind an API gateway
  • Data processing: lightweight workers for streams or batched jobs
  • Scheduled tasks: cron-like jobs for maintenance or reports
  • Orchestrated workflows: small steps coordinated by a state machine These patterns emphasize small, idempotent units and clear boundaries.

Example A user uploads a photo. A storage event triggers a function to resize the image, another function updates the catalog, and a final step sends a notification. Each function runs independently and can scale or retry without affecting others.

Choosing patterns

  • Match workload characteristics: bursty vs steady load
  • Consider latency sensitivity and memory needs
  • Plan for observability: logs, traces, metrics
  • Design for idempotence, retries, and graceful failure

Bottom line Serverless shines for event-driven, scalable workloads and rapid delivery. For long-running tasks or strict control over runtime, hybrid or container-based approaches can work well.

Key Takeaways

  • Serverless can reduce ops and cost for many apps, but watch latency, vendor lock-in, and testing complexity
  • Use patterns like event-driven functions and orchestrations to keep code modular
  • Plan around observability, security, and clear boundaries between services